cssi/SciSciGPT-SciSciNet huggingface dataset:
Glucocorticoids fail to inhibit arachidonic acid metabolism stimulated by hydrogen peroxide in the alveolar macrophage.

We have previously demonstrated that the biologically important oxidant hydrogen peroxide (H202) triggers release and metabolism of arachidonic acid (AA) in the alveolar macrophage (AM). In this study, we evaluated the ability of glucocorticoids to inhibit rat AM AA metabolism stimulated by H2O2, as compared to the particulate zymosan. Methybprednisobone and other glucocorticoids failed to significantly inhibit release of AA stimulated by H2O2, while markedly reducing AA release in response to zymosan. Similarly, methylprednisobone only weakly inhibited synthesis of thromboxane (Tx)B2 stimubated by H202, while inhibiting zymosan-induced eicosanoid synthesis to a marked degree. On the other hand, the phospholipase inhibitor mepacrine strongly Inhibited AA release and TxB2 formation stimulated by both H202 and zymosan, indicating that H202induced AA metabolism is indeed susceptible to pharmacologic inhibition. The failure of glucocorticoids to inhibit AA metabolism stimulated by H2O2 in the AM may in part explain their inability to ameliorate oxidant-mediated lung inflammation and injury.
Intra-Industry Effects of IPOs on Stock Repurchase Decisions of Rival Firms

Previous studies suggest that the market perceives IPOs as bad news to existing firms in the same industry. However, investors tend to be overly optimistic about IPO prospects, especially during hot IPO markets. Thus, the negative industry rival reaction could be the result of investors’ over-optimism about the IPOs’ prospects and underestimation of the competitive positions of industry rivals. Our findings show that rival firms use repurchases to correct for the market’s overreaction to the IPO threat. These IPO-induced repurchases are stronger when the rival firms are in a concentrated industry and experienced poor stock performance in the previous year.
WITHDRAWN: Current opinion in the role of testosterone in the development of prostate cancer: A dynamic model

Abstract Since the landmark studies conducted by Huggins and Hodges in 1941, a failure to distinguish the etiological role of testosterone from its role in prostate cancer progression has led to the prevailing opinion that high levels of testosterone increase the risk of prostate cancer. To date, this claim remains unproven and epidemiological evidence is inconsistent. In this study, we present a novel dynamic model regarding the relationship between testosterone and prostate cancer to advance our understanding of the current findings and to guide future prostate cancer research. In our model, we theorize that it is the magnitude of the age-related declines in testosterone rather than the static level of testosterone measured at a single point that may trigger and promote the development of prostate cancer. After body testosterone falls below a threshold level, the prostate cells cannot maintain their normal functions and eventually some turn into tumor cells. Individual threshold of testosterone may be positively associated with a peak testosterone level of this individual during young adulthood. Our dynamic model can satisfactorily explain the observed age pattern of prostate cancer incidence, the seemingly conflict of findings from epidemiological studies on testosterone and risk of prostate cancer, racial disparities in prostate cancer incidence, many risk factors associated with prostate cancer, and the role of testosterone in prostate cancer growth. Our dynamic model may also have implications for testosterone replacement therapy. We conclude that this dynamic model provides a new perspective to enhance our understanding the role of testosterone in the onset and development of prostate cancer, to guide future studies, and to promote and improve testosterone replacement therapy in prevention of prostate cancer.
A computational study of seat and seatbelt performance for protecting 6-12 year-old children in frontal crashes

The purpose of this study is to examine the effects of the body size for 6-12 year-old children as well as belt and seat design factors on injury outcomes in frontal crashes using computational simulations. Custom software was created to automatically scale and position a MADYMO child dummy model with an improved pelvis and abdomen geometry from child data. A parametric analysis of the effects from child size, seat belt anchorage locations, seat cushion length and seat stiffness on the injury predictors of child passengers aged between 6 and 12 in the FMVSS213 crash scenario was conducted. Child size was the dominant variable affecting the outcome measures. Seat design variables and the seat belt system variables had opposing effects on outcome measures, particularly between head and knee excursions, highlighting the importance of using optimisation techniques for future seat belt and seat designs to improve rear seat older child protection.
NFκB is persistently activated in continuously stimulated human neutrophils

Increased activation of the transcription factor NFκB in the neutrophils has been associated with the pathogenesis of sepsis, acute lung injury (ALI), bronchopulmonary dysplasia (BPD), and other neutrophil-mediated inflammatory disorders. Despite recent progress in analyzing early NFκB activation in human neutrophils, activation of NFκB in persistently stimulated neutrophils has not been previously studied. Because it is the persistent NFκB activation that is thought to be involved in the host response to sepsis and the pathogenesis of ALI and BPD, we hypothesized that continuously stimulated human neutrophils may exhibit a late phase of NFκB activity. The goal of this study was to analyze the NFκB activation and expression of IκB and NFκB proteins during neutrophil stimulation with inflammatory signals for prolonged times. We demonstrate that neutrophil stimulation with lipopolysaccharide (LPS) and tumor necrosis factor-α (TNFα) induces, in addition to the early activation at 30–60 min, a previously unrecognized late phase of NFκB activation. In LPS-stimulated neutrophils, this NFκB activity typically had a biphasic character, whereas TNFα-stimulated neutrophils exhibited a continuous NFκB activity peaking around 9 h after stimulation. In contrast to the early NFκB activation that inversely correlates to the nuclear levels of IκBα, however, in continuously stimulated neutrophils, NFκB is persistently activated despite considerable levels of IκBα present in the nucleus. Our data suggest that NFκB is persistently activated in human neutrophils during neutrophil-mediated inflammatory disorders, and this persistent NFκB activity may represent one of the underlying mechanisms for the continuous production of proinflammatory mediators.
A Study of Fibroblast Growth Factor and Its Receptor Complex Using Light Scattering

Dynamical light scattering technique was used to study the interaction of fibroblast growth factor and its receptor proteins in solution.
Equations of motion and continuity for fluid flow in a porous medium

This paper is devoted to a rigorous derivation of the fundamental laws governing the macroscopic flow of fluids in a porous medium. The derivation is given within the framework of classical continuum mechanics and the resulting equations contain the continuity equation and the Euler equations of motion of hydrodynamics as well as Darcy's law as special cases.
Simple Renal Cysts in Children

AbstractSimple renal cysts in childhood are uncommon and often are confused with duplication anomalies or renal malignancy. A review of 20 children with simple renal cysts at our institution has documented the spectrum of clinical presentations and radiographic findings of this unusual renal mass. Surgical exploration and marsupialization of the cyst wall were done in 12 patients, 4 underwent nephrectomy earlier in our series and 4 have been followed conservatively by ultrasonography or computerized tomography scanning. Although equivocal cases necessitate surgical intervention, we advocate conservative therapy with diagnostic ultrasonography with or without cyst puncture in asymptomatic and normotensive children with simple renal cysts.
Transmitter-Side Digital Back Propagation With Optical Injection-Locked Frequency Referenced Carriers

A 100% reach extension is demonstrated in a coherent four-channel wavelength division multiplexed system by employing full-bandwidth frequency-referenced transmitter-side digital back propagation. Frequency referenced optical carriers are generated by injection locking distributed feedback lasers to a reference optical frequency comb and the performance of digital back propagation is evaluated with and without the frequency reference. In addition, we investigate the effect of an implementation with reduced computational complexity by limiting the number of steps-per-span used in the back propagation computation. Lastly, we measure the penalties generated by an inaccurate fiber dispersion parameter in the back propagation model.
Relationship between Plasma Renin and Cortisol in Hypertensive Patients

1. Plasma cortisol at 08.00 hours was significantly higher (P less than 0.005) in patients with high-renin essential or renovascular hypertension (22.6 +/- 1.6 microgram/100 ml) than in patients with normal-renin (15.4 +/- 1.2) or low-renin (11.9 +/- 1.2) forms of hypertension. 2. Plasma cortisol at 12.00 or 16.00 hours did not differ significantly among the three groups; thus the diurnal swing in plasma cortisol was steepest in patients with high plasma renin. 3. Among all patients studied, there was a direct relationship between 08.00 hours plasma cortisol and ambulatory plasma renin activity (r = 0.65, P less than 0.001). 4. In patients with high-renin values, 08.00 hours plasma cortisol fell by 39 +/- 6% after 10 days treatment with the converting enzyme inhibitor captopril. No consistent decreases were observed in the normal- or low-renin groups. 5. We conclude that the renin--angiotensin system may interact with the pituitary--adrenal axis to influence circulating levels of cortisol. This effect might conceivably contribute to the pathogenesis of certain high-renin states.
Abstract A12: Challenges to patient-centered care for limited English proficient breast cancer patients

Background: Provision of high quality patient-centered care is fundamental to eliminating healthcare disparities in breast cancer. This is particularly true for the large and growing population of women with limited English proficiency (LEP). These women are less likely to experience patient-centered care because their communication with their physicians is complicated by a language barrier. We set out to investigate physicians9 experiences communicating with LEP breast cancer patients, and to assess their perceived difficulty in discussing treatment options and prognosis across a language barrier Methods: We conducted a survey of a representative sample of California physicians by randomly selecting 1250 surgeons and oncologists from the American Medical Association Masterfile. Physicians were excluded if they spent Results: Of the 313 respondents (50% participation rate), 301 reported having some patients in their panel (mean 19%, s.d. 19; range 1–98%) with a limited ability to communicate in English. Of those 301 respondents, 58% were surgeons, 75% were male, and 67% were in private practice. They had been in practice on average 19 years (s.d. 10, range 2–50); and, on average 33% (s.d 23, range 10–100) of their patients had breast cancer, and 21% (s.d. 16, range 0–95) had less than a high school education. Of the 173 physicians who reported ever speaking directly with patients in a non-English language, only two-thirds reported adequate language skills to do so. Additionally, only 40% reported often/sometimes using any kind of professional interpretation services (in-person, telephonic, videoconferencing). Half (52%) reported setting aside extra time for visits with LEP patients. Although 75% of physicians surveyed felt they were usually able to communicate effectively when treating a breast cancer patient who is LEP, 47% said they tend to be more directive about treatment recommendations, 54% said they tend to simplify their discussion of risks and benefits, and 64% worry that their LEP patients may not have asked all of their questions. Many more physicians reported difficulty discussing both treatment options and prognosis with LEP patients (59% and 57%) than with patients either from a different culture (25% and 33%) or with a low level of education (24% and 29%). Conclusions: California oncologists and surgeons caring for breast cancer patients find communication about both treatment options and prognosis markedly more challenging when it takes place across a language barrier than across cultures or education levels. Despite this, the majority of respondents do not use professional interpreters, even over the telephone; and many of them simplify important discussions with their LEP patients, worrying that these women are not asking all of their questions. In addition to increased access to, reimbursement for, and use of professional interpreters, these physicians and their LEP patients may benefit from the development and implementation of best practice communication tools to assist in complex treatment and prognosis discussions.
0.89 mW on-chip jitter-measurement circuit for high speed clock with sub-picosecond resolution

This paper demonstrates an all digital fully on-chip jitter measurement circuit with sub-picosecond resolution that can be used with or without an external reference. The circuit is integrated on a CMOS chip and outputs a digital code proportional to the jitter of high speed clock signals. It achieves low error while consuming less than 0.89 mW by using a low-speed stochastic under-sampler to approximate high speed sampling. Test chips were fabricated in a 65 nm CMOS process with an active area of 0.015 mm2. The absolute jitter and period jitter of a 6 GHz test clock were measured with root mean square error of 0.102 ps and 0.308 ps, respectively.
Household ceramic diversity in the late prehistory of the Appalachian Summit

ABSTRACTPottery from the Ward site village (31WT22; ca. A.D. 1100) in mountainous northwestern North Carolina exhibits remarkable synchronic diversity that evokes speculations about prehistoric social institutions. Large fragments of ceramic jars recovered from the base of a storage pit at a nearby single house site appear to represent the wares of one household dating to approximately A.D. 1350. Like the Ward site pottery, diverse tempering materials and surface treatments at this site defy existing typologies and show that individual artisans availed themselves of a palette of technological and stylistic choices, some of which were introduced through interaction with neighboring Mississippian and Woodland groups, especially those lying to the south and east.
Chapter 3.9 – Prediction of failure envelopes and stress/strain behavior of composite laminates*

Publisher Summary This chapter presents failure envelopes for unidirectional composites and multilayered composite laminates, which have been predicted by linear laminate theory. There are three major failure modes in composites—namely, fiber failure, matrix failure, and fiber/matrix interfacial failure. Because, in general, the stresses in the fiber and matrix are different; their respective failures are determined by different stresses and have different failure mechanisms. Thus, a lamina failure criterion that separates matrix failure from fiber failure, such as the Hashin–Rotem criterion, is mechanistically more appropriate. The ply-by-ply discount method with parallel spring stiffness reduction model is used in the prediction. Laminate ply-by-ply failure analysis is performed on the basis of the 2-D stress field in the laminate. The stress/strain behavior of four laminates under uniaxial or biaxial loading is predicted by considering both material nonlinearity and progressive matrix cracking. Material nonlinearity is considered by using a one-parameter plasticity model for fiber reinforced composites. Progressive matrix cracking and the corresponding stiffness reduction are predicted by the use of a simplified shear-lag analysis and finite element analysis.
Methods of Calculation of Energy Bands in Solids

These lectures present a review of the basic principles and methods of the calculation of energy bands. The procedures in current use are surveyed briefly. Recent developments are noted. The problems of the construction of a crystal potential are examined in regard to the representation of the exchange interaction.
Fragmentation and the Role of Seed Banks in Promoting Persistence in Isolated Populations of Collinsia verna

Plant species that inhabit environments characterized by environmental stochasticity and/or catastrophe have evolved two common bet-hedging strategies: one based on seed dispersal attributes and one on dormancy attributes, which lead to the formation of a soil seed bank. The environmental conditions that select for the evolution of spatial versus temporal dispersal will depend on both the magnitude of the environmental variance and the spatial array of suitable habitat patches. In species that normally are connected as a metapopulation, repeated local extinction occurs, and recolonization of the available habitat patches is accomplished by seed dispersal. In a metapopulation structure, individuals are distributed among a series of subpopulations that are connected to one another by dispersal. The number of individuals in each subpopulation fluctuates according to local demogrpahic conditions, and subpopulations can fluctuate largely independently. These fluctuations in numbers of individuals may periodically extirpate a subpopulation, but persistence of a species in such a subpopulation is enhanced because dispersing individuals from other subpopulations can recolonize an extirpated area. Thus metapopulation structure and function enhances the regional persistence of species in spatially and temporally variable environments (Hanski and Gilpin 1991). Spatiotemporal variability in subpopulation size and persistence probability favors the evolution of high dispersal rates among subpopulations (Gadgil 1971, Cohen and Levin 1991, den Boer 1987, McPeek and Holt 1992). High dispersal rates will enhance the persistence of the entire metapopulation by increasing the recolonization rate of extinct subpopulations (Hanski and Gilpin 1991, den Boer 1987, McPeek and Holt 1992, Ebenhard 1991, Verboom and Lankester 1991, Hanski 1991). However, if the distance among subpopulations exceeds the dispersal capacity of the organism and the probability of successful recolonization is low, the evolution of dormancy will be favored.
Changing Natural History of HER2-Positive Breast Cancer Metastatic to the Brain in the Era of New Targeted Therapies.

Abstract Background Given the wide adoption of human epidermal growth factor receptor 2 (HER2)-targeted therapies for advanced HER2–positive breast cancer, we studied the natural history of patients with HER2–positive breast cancer brain metastases (BCBM) over time. Patients and Methods Patients with HER2–positive BCBM identified from a prospectively maintained database at the University of North Carolina were divided into 3 cohorts by year of BCBM diagnosis. Cohorts were selected by year of HER2–targeted therapy US Food and Drug Administration approval. Overall survival (OS), time to first metastasis, time to BCBM, and BCBM survival were estimated by the Kaplan-Meier method. Associations between OS after BCBM and clinical variables were assessed by Cox proportional hazards regression models. Results One hundred twenty-three patients were identified. Median age was 51 years, and 58% were white and 31% African American. OS from initial breast cancer diagnosis improved over time: 3.6 years (95% confidence interval [CI], 2.8-6.1) in the 1998-2007 cohort, 6.6 years (95% CI, 4.5-8.6) in the 2008-2012 cohort, and 7.6 years (95% CI, 4.4-9.6) in the 2013-2015 cohort (P = .05). While time from initial diagnosis to first metastasis did not differ (P = .12), time to BCBM increased over time (2.6 years [95% CI, 1.3-3.5] for 1998-2007; 2.6 years [95% CI, 2.1-4.3] for 2008-2012, and 3.3 years [95% CI, 2.2-6] for 2013-2015; P = .05). Although OS from BCBM did not significantly differ by cohort, patients who received HER2–targeted therapy after BCBM had a prolonged OS (2.1 years [95% CI, 1.6-2.6] vs. 0.65 years [95% CI, 0.4-1.3]; P = .001). Conclusion OS from initial breast cancer diagnosis significantly improved over time for patients with HER2–positive breast cancer who develop BCBM, now exceeding 7 years; survival from BCBM diagnosis may now exceed 2 years.
Some Experiences with Labeling Nucleotides

Several years ago it became apparent that uridine nucleotides containing various carbohydrate moieties were the probable precursors of polysaccharides. This observation followed largely from the initial work of Leloir and his collaborators [1] and of Park [2]. Work by Cifonelli and Dorfman [3] showed that Group A streptococci contain UDP-glucuronic acid (UDPGA), UDP-N-acetylglucosamine (UDPAG), and UDP-N-acetylmuramic acid. The first two, UDPGA and UDPAG, contain the constituent monosaccharides of hyaluronic acid (HA), an acid mucopolysaccharide that occurs in connective tissues and in the capsule of certain Group A streptococci. Although reasonable quantities of the nucleotide precursors of HA were available, labeling with C14 would have been both difficult and time consuming.
Predicting Field Degradation of Sealants Using Accelerated Tests from the NIST Solar Sphere

Abstract Field testing of sealants, used for instance in construction, is a slow process due primarily to the good durability of these materials. The tempo of the development cycle for such materials could be greatly increased by accelerating their degradation in laboratory conditions and then translating that degradation to a field prediction. Efforts to this end have been, and continue to be, explored at the National Institute of Standards and Technology (NIST) as part of the sealant consortium. The results so far are mixed, but the final goal of accurate field predictions has yet to become a reality. In this chapter, efforts to date, as well as future plans are described. Efforts to date include modeling of accelerated degradation data from the NIST solar sphere, as well as an initial approach to translating predictions from the model to the field. They also include a process for creating maps of predicted field degradation throughout the contiguous United States. Future plans include modifying the initial translation procedure to include measurements of solar intensity and understanding possible differences between mechanical strain applied in the laboratory and realized outdoors.
The non-indigenous ant, Solenopsis invicta, reduces loggerhead shrike and native insect abundance

The red imported fire ant (Solenopsis invicta Buren) is an aggressive, non-indigenous species that is a threat to native biota in the south- eastern United States. We determined the effect of S. invicta on loggerhead shrike (Lanius ludovicianus L.) abundance and investigated a possible mecha- nism of impact, which is a reduction in insect prey availability. We used a fire ant bait (hydramethylnon) to reduce fire ant populations on one randomly chosen member of each of five pairs of 202-ha study areas in the Texas coastal Bend region, and also measured shrike relative abundance and a volumetric index of insect biomass on the study areas. Loggerhead shrike relative abun- dance was assessed at five counting stations established along 3.2-km transects through prairie habitat on each study area during the fall of 1992 and 1993. We sampled non-S. invicta invertebrates with 13.3-L capacity UV light traps and found that insect volume, species richness, and diversity were greater on treated sites. More shrikes were observed on areas where S. invicta populations had been reduced. Both insect biomass and shrike abundance were negatively correlated to the level of S. invicta infestation. Our data sug- gest that shrikes may avoid areas on wintering habitats that have been in- vaded by S. invicta and that this avoidance may result from reduced insect availability.
Naive Bayes as a Masquerade Detector: Addressing a Chronic Failure

Masquerade detection undertakes to determine whether or not one computer user has impersonated another, typically by detecting significant anomalies in the victim’s normal behavior, as represented by a user profile formed from system audit data, command histories, and other information characteristic of individual users. Among the many intrusion/masquerade-detection algorithms in use today is the naive Bayes classifier, which has been observed to perform imperfectly from time to time, as will any detector. This paper investigates the prospect of a naive Bayes flaw that prevents detection of attacks conducted by so-called “super-masqueraders” whose incursions are consistently undetected across an entire range of victims. It is shown in this paper, through controlled experimentation and a rigorous mathematical exposition, that a weakness in the detector causes it to miss attacks under certain conditions. Furthermore, meeting those conditions – and crafting an undetectable attack – is often entirely within the control of the attacker. This paper also demonstrates, however, that such attacks can be overcome by fortifying the algorithm with a diverse detection capability. The “fortified” detector improves detection and, more significantly, removes the threat of the supermasquerader, virtually eliminating the impact of the algorithm’s defect.
Aqueous flow in humans after adrenalectomy.

PURPOSE This study was performed to determine if the circadian rhythm of aqueous humor formation and the aqueous humor suppressing effect of beta-adrenergic antagonists can occur in the absence of adrenally derived epinephrine. METHODS Twenty-one human subjects who had undergone bilateral adrenalectomy were studied during a 28-hour period. The study was divided into four time periods as follows: morning 1 (8 AM to noon), afternoon (noon to 4 PM), night (midnight to 6 AM), and morning 2 (8 AM to noon). At 6:45 AM before the morning 2 measurements, one drop of 0.5% timolol was applied to one eye and one drop of placebo (artificial tears) was applied to the other eye. Topical fluorescein and a scanning fluorophotometer were used to measure the rate of aqueous humor flow. Twenty normal controls were studied in a similar fashion but did not undergo the morning 2 measurement. RESULTS In the subjects lacking adrenals, the daytime rates of aqueous flow were 3.17 +/- 0.78 microliters/min (mean +/- SD) and 3.16 +/- 0.67 microliters/min for the morning 1 and afternoon periods, respectively. The rates in daytime periods were not significantly different from each other (P = 0.699). The rate of aqueous flow for the night period was 1.37 +/- 0.37 microliters/min, a 57% reduction from both morning 1 and afternoon periods (P < 0.001). The morning, afternoon, and night rates of flow in normal controls were not significantly different from the rates in subjects lacking adrenals. For the morning 2 period, the aqueous flow was 2.74 +/- 0.54 microliters/min for the placebo-treated eye and 1.77 +/- 0.38 microliters/min for the timolol-treated eye. The rate of aqueous flow was reduced (35%) in the timolol-treated eye when compared to the fellow placebo-treated eye (P < 0.001). The timolol-treated eye also showed a 26% reduction in intraocular pressure when compared to the fellow placebo-treated eye (P < 0.001). CONCLUSION The study demonstrates that both the circadian rhythm of aqueous flow and the daytime response to timolol persist in the absence of the adrenal glands.
Arthroscopic Capsular Release for Shoulder Stiffness

Shoulder stiffness can result due to primary idiopathic adhesive capsulitis or secondary to known intrinsic, extrinsic, or systemic conditions (including posttraumatic stiffness and postoperative stiffness). Primary idiopathic adhesive capsulitis Considered a painful self-limiting disease that resolves after 1–3 years. Incidence is estimated to be around 2–5% in the general population. Women comprise approximately 70%. Contralateral shoulder is likely to be involved in 20–30% of patients. Pathology results from intraarticular inflammation and fibrosis which causes contracture of the capsule and a reduced intraarticular volume. It is believed to result from a systemic disorder (inflammatory, endocrine, immunologic, biochemical), although a definite etiology is not known. Hannafin and Chiaia described four stages of adhesive capsulitis: Stage 1: “Initial painful phase” (0–3 months) – pain with active and passive ROM, some limitation of movements Stage 2: “Freezing stage” (3–9 months) – chronic pain with active and passive ROM, significant limitation of movements Stage 3: “Frozen stage” (9–15 months) – minimal pain except at end ROM, significant limitation of ROM with rigid “end feel” Stage 4: “Thawing stage” (15–36 months) – minimal pain, progressive improvement in ROM Secondary adhesive capsulitis can result in global loss of active and passive ROM or reduced ROM in specific plane depending on the etiology. Asymmetric loss of motion results from scarring in the area affected Contracture may be intraarticular or extraarticular. Particular pattern of limitation in ROM can assist with planning rehabilitation protocol or particular operative management Reduced external rotation in adduction suggests contractures of the anterosuperior capsule and the rotator interval Loss of external rotation in abduction is associated with contractures of the anteroinferior capsule Decreased internal rotation in abduction or adduction and reduced cross-chest adduction is indicative of posterior capsular contractures
Reinforcement Learning for Autonomous UAV Navigation Using Function Approximation

Ahstract- Unmanned aerial vehicles (UAV) are commonly used for search and rescue missions in unknown environments, where an exact mathematical model of the environment may not be available. This paper proposes a framework for the UAV to locate a missing human after a natural disaster in such environment, using a reinforcement learning (RL) algorithm. A function approximation based RL algorithm is proposed to deal with a large number of states representation and to obtain a faster convergence time. We conducted both simulated and real implementations to show how the UAVs can successfully learn to carry out the task without colliding with obstacles. Technical aspects for applying RL algorithm to a UAV system and UAV flight control were also addressed.
Synthesis of (-)-(R)-pyrrolam a and studies on its stability: a caveat on computational methods.

The asymmetric synthesis of (−)-(R)-pyrrolam A was achieved in three operations from N-Boc pyrrolidine via an α-(N-carbamoyl)alkylcuprate vinylation reaction followed by N-Boc deprotection and cyclization. One-pot deprotection−cyclization procedures led to mixtures of pyrrolam A and its double bond isomers. These isomerization events could be circumvented by use of a two-step procedure. To guide aspects of the experiments, a series of computational energy evaluations and chemical shift predictions were performed with molecular mechanics, semiempirical, ab initio, and density functional methods. The relative stabilities of the double bond isomers, as estimated by experiment, challenged a number of computational methods, and only the MP2 model with its moderate degree of electron correlation came close to matching the experimental data. The MP2 method was further applied to an unusual aspect of the double bond migration between pyrrolam A and its isomer 9. The reaction (1 to 9) on neat samples is irreversib...
“tsɑrɑŋ?” - Telephone Conversation Openings in the Rushani Language

This paper uses conversation analysis (CA) to examine telephone conversation openings in an unwritten and understudied language, Rushani, spoken primarily in remote, mountainous areas of Tajikistan and Afghanistan. In a sample of three telephone conversations, examples are sought of the four opening sequences of telephone calls originally identified by Schegloff (1986): summons-answer; identification-recognition; greetings; and initial inquiries. At first glance, telephone conversation openings in Rushani appear to skip over the greeting stage and move directly into an extended exchange of initial inquiries. However, upon closer analysis, it is argued that a Rushani word that translates as “How are you” is in fact used by conversation participants as a greeting. The paper concludes with an argument that the study supports a “universalist” position of CA as applied to calls conducted in languages other than English (Luke & Pavlidou, 2002). Despite their apparent form as initial inquiries, greetings in telephone conversations in Rushani serve precisely the same function and resolve the same “interactional issues” as greetings in other languages (Schegloff, 1986).
Coronary Heart Disease

Coronary heart disease (CHD) is the comprehensive term which includes all of the clinical manifestations that result from atherosclerotic1 narrowing or occlusion of the arteries which supply the heart muscle. The hallmark of clinically manifest atherosclerosis is the progressive deposition of cholesterol as plaques in artery walls. Eventually this leads to secondary changes. Fibrous scar tissue and calcium may accumulate (hence the “hardening”), or the plaques may become necrotic and abscess-like if they outstrip their blood supply. Then hemorrhage into the softened plaque may result in rapid increase in lesion size or the contents may erupt to the surface. If the bloodstream interface of the deposit breaks down, large pieces of cholesterol debris may flake off into the circulation, occluding vessels downstream, and there may be thrombus2 formation on the rough ulcer surface. When thrombosis occurs in coronary arteries the thrombus usually totally occludes the vessel, producing a myocardial infarction.3
Assessment of Human Dynamic Gait Stability With a Lower Extremity Assistive Device

This paper focuses on assessing gait stability by metrics derived from dynamical systems theory to understand the influence of unilateral robot assistance on the human walking pattern. A motorized assistive robot is applied to the right knee joint to provide stance support. The metrics related to global stability (the maximum Floquet multiplier, max FM), local stability (short-term and long-term divergence exponents, $\lambda _{\text {s}}$ and $\lambda _{\text {l}}$ ), and variability (median absolute deviation, MAD) are considered. These metrics are derived for bilateral hip, knee, and ankle joint angles. Additionally, a biomechanical metric, the minimum margin of stability is assessed. Experiments are conducted on 11 healthy participants with different robot controllers. The max FM and $\lambda _{\text {s}}$ yield statistically significant results, showing that the unassisted (left) leg is more stable in right knee assistance conditions when compared to the normal walking condition due to inter-limb coordination. Moreover, MAD and $\lambda _{\text {l}}$ show that the variability and chaotic order of walking pattern during assistance are lower than those of normal walking. The proposed control strategy (automatic impedance tuning, AIT) improves local and orbital gait stability compared to existing controllers such as finite-state machine (FSM). The assessment of dynamic gait stability presented in this paper provides insights for further improving control strategies of assistive robots to help a user reach improved gait stability while maintaining appropriate variability.
Ambitious and Anxious: : How Chinese College Students Succeed and Struggle in American Higher Education

Over the recent decade, the United States has witnessed a growing influx of self-funded Chinese international undergraduate students into its university campuses. Mainstream U.S. media accounts have tended to hold unexamined stereotypes about these international students. This essay review of Ambitious and Anxious: How Chinese College Students Succeed and Struggle in American Higher Educationhighlights the importance of exploring students’ agency in their pursuit of international education. The article points out that to better understand Chinese international undergraduate students’ ambition and anxiety, we must link their emotional and psychological burdens, their academic and social struggles, as well as their agency, to the changing national and international contexts where these students’ transnational mobility is situated. The essay also calls for the need for further research into the politics of international student mobilities.
Source Switching Maintains Dissolved Organic Matter Chemostasis Across Discharge Levels in a Large Temperate River Network

Dissolved organic matter (DOM) helps regulate aquatic ecosystem structure and function. In small streams, DOM concentrations are controlled by transport of terrestrial materials to waterways, and are thus highly variable. As rivers become larger, the River Continuum Concept hypothesizes that internal primary production is an increasingly important DOM source, but direct evidence is limited. Recently, the Pulse-Shunt Concept postulated that terrestrial DOM concentrations in larger rivers increase with flow and temperature, which seemingly contradicts previously reported DOM chemostasis in large rivers. This study estimates daily gross primary production (GPP) in 13 streams and rivers across the Connecticut River watershed (watershed areas 0.4–25,019 km2) from 2015 through 2017. Chemostasis of DOM concentrations is maintained by a switch from autochthonous sources of DOM at low flows to terrestrial sources of DOM at high flows in a large temperate river and to a lesser degree in smaller tributaries. At low flow, autochthonous DOM linked to aquatic GPP is the dominant fraction of the DOM pool in large rivers. This autochthonous DOM maintains chemostasis in the main stem and to a lesser extent upstream. Thus, in larger rivers, low-flow autochthonous production stabilizes DOM concentrations during the summer, a critical time for riverine ecology. Consistent with the Pulse-Shunt Concept, terrigenous DOM is the dominant fraction of DOM during higher flow periods and about 70% of annual DOM fluxes to the coast are terrestrial. This pattern of DOM switching is potentially widespread in temperate watersheds with implications to both inland waters and coastal ecosystems.
Adverse Events and Modes of Failure Related to Rotational Atherectomy System: The Utility of the MAUDE Database.

Background/purpose Coronary artery calcification is a marker of advanced atherosclerosis and a predictor of adverse clinical outcomes. Rotational atherectomy (RA) can effectively modify calcified lesions, optimizing procedural outcomes. We interrogated the most commonly reported adverse events involving rotational atherectomy systems (Rotablator and Rotapro) by analyzing post-marketing surveillance data from the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) database. Methods/materials We queried MAUDE from September 1, 2016, through December 31, 2019. After excluding duplicate reports, we included 363 reports for Rotablator and 63 reports for Rotapro in the final analysis. Results Percentages represent the proportion of total submitted MAUDE reports. The most commonly reported complications for Rotablator and Rotapro included dissection (2.7% and 6.3%, respectively) and perforation (4.1% and 19%, respectively). The most commonly reported device-related issues included detachment or structural damage, or both, for Rotablator (39.1%) and entrapment of the device component for Rotapro (47.6%). The most commonly damaged device component was the Rotawire, whereas the most commonly entrapped device component was the Rotaburr for both device configurations. Rotablator and Rotapro device-related complications were most commonly reported for the left anterior descending artery. Conclusion An analysis of the MAUDE database demonstrates that in real-world practice, RA devices are associated with important complications. Ongoing surveillance of safety profiles, patient outcomes, and failure modes of RA devices is warranted. Our analysis provides important insights into the mechanisms of failure of RA devices and associated complications but cannot verify causality. Summary We interrogated the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) database to summarize the most commonly reported adverse events and device-related issues associated with the rotational atherectomy systems (Rotablator and the newer iteration, Rotapro). The MAUDE database serves as an important tool for improved collaboration between clinicians, device manufacturers, and regulatory bodies to optimize device safety and patient outcomes.
Iterated projected position algorithm for constructing exponentially localized generalized Wannier functions for periodic and nonperiodic insulators in two dimensions and higher

Localized bases play an important role in understanding electronic structure. In periodic insulators, a natural choice of localized basis is given by the Wannier functions which depend on a choice of unitary transform known as a gauge transformation. Over the past few decades, there have been many works that have focused on optimizing the choice of the gauge so that the corresponding Wannier functions are maximally localized or reflect some symmetry of the underlying system. In this work, we consider fully nonperiodic materials where the usual Wannier functions are not well defined and gauge optimization is impractical. To tackle the problem of calculating exponentially localized generalized Wannier functions in both periodic and nonperiodic systems, we discuss the `iterated projected position (IPP)'' algorithm. The IPP algorithm is based on matrix diagonalization and therefore unlike optimization-based approaches, it does not require initialization and cannot get stuck at a local minimum. Furthermore, the IPP algorithm is guaranteed by a rigorous analysis to produce exponentially localized functions under certain mild assumptions. We numerically demonstrate that the IPP algorithm can be used to calculate exponentially localized bases for the Haldane model, the Kane-Mele model (in both ${\mathbb{Z}}_{2}$ invariant even and ${\mathbb{Z}}_{2}$ invariant odd phases), and the ${p}_{x}+i{p}_{y}$ model on a quasicrystal lattice.
Cybernetic modeling of biological processes in mammalian systems

Regulation of metabolism in mammalian cells is achieved through a complex interplay between cellular signaling, metabolic reactions, and transcriptional changes. The modeling of metabolic fluxes in a cell requires the knowledge of all these mechanisms, some of which may be unknown. A cybernetic approach provides a framework to model these complex interactions through implicit accounting of such regulatory mechanisms, assuming a biological ‘goal’. The premise underlying the cybernetic framework is that the regulatory processes affecting metabolism can be mathematically formulated as a cybernetic objective through variables that constrain the metabolic reaction network to achieve a specified biological ‘goal’. Here, we highlight the utility of the cybernetic framework in modeling of prostaglandin metabolism in murine macrophage cells during inflammation. We present a perspective for future use of the cybernetic framework for modeling complex cellular processes using multiple objectives, which can represent distinct subprocesses within the metabolic reaction network.
No longer a wacky foreigner: Study abroad, communities of practice, and second language learning

Abstract This study focuses on language socialization during study abroad and specifically second language learning in communities of practice. Based on oral interviews in French and English, written journals, and weekly surveys, this study examines one participant’s second language (L2) learning during a semester abroad during which he became a member of two communities of practice: his host family and a local gaming group. The participant negotiated and became more confident in his L2 identity and learning over time and increasingly solidified his membership within these groups. This study analyzes the steps taken by the participant using the framework of legitimate peripheral participation and considers identity and learning that develop within a community of practice.
Growth Competition in Interspecies Chimeras: A New Paradigm for Blastocyst Complementation.

Summary Blastocyst complementation represents a powerful technique for interspecies organogenesis but is limited by low chimerism due to developmental incompatibilities. In this issue of Cell Stem Cell, Nishimura et al. (2021) circumvent early developmental barriers by disabling Igf1r in host embryos, conferring donor cells with a growth advantage from mid-gestation onward.
Beyond babies: Implications of human genome editing for women, children, and families

Scholarship on human germline editing has centered on the risks to the genetically-modified child. However, far less emphasis is focused on women who will become pregnant with a genetically modified embryo as part of human subject research or the families that raise children whose genomes were modified as an embryo. The lack of attention on women and families places these key stakeholders in genomic technologies at significant medical, ethical, and personal harm as research rapidly moves forward to advance the science of genomic modification. Now is the time to address how the interests of women and families should be represented in the ethical and scientific frameworks of human genomic modification, with specific considerations for Institutional Review Boards who review protocols for rigorous human subject protections and scientists who develop scientific methodologies that dictate the potential risks conferred to research participants. In this paper, we examine the implications of genomic modification of human embryo for women, children, and families to explore how to review a first-in-human clinical protocol of human genomic officiation responsibly.
The Time is at Hand: Literacy Predicts Changes in Children's Gestures About Time.

The metaphorical motion of time can be expressed in gesture along either a sagittal axis—with the future ahead and past behind the speaker, or a lateral axis—with the past to the left and future to the right of the speaker (Casasanto & Jasmin in CL 23(4): 643–674, 2012). Adult English speakers, when gesturing about time, show a preference for lateral gestures with left-to-right directionality, consistent with the directionality of the reading-writing system in English (Casasanto & Jasmin in CL 23(4): 643–674, 2012). In this study, we asked how early children would show a preference for left-to-right lateral gestures and whether literacy skills would predict the production of such gestures. Our findings showed developmental changes in both the orientation and directionality of children’s gestures about time. Children increased their production of left-to-right lateral gestures over time, with a shift around ages 7–8. More importantly, literacy predicted children’s production of such lateral gestures. Overall, these results suggest that the orientation and directionality of children’s metaphorical gestures about time follow a developmental pattern that is largely influenced by changes in literacy.
Disparities in Patient-Centered Communication via Telemedicine.

Purpose: This study investigated disparities in the uptake of telemedicine and the degree of patient-centeredness of telemedicine consultations among vulnerable patient populations. The focus inclu...