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The Critical Success Index (CSI) and Gilbert Skill score (GS) are verification measures that are commonly used to check the accuracy of weather forecasting. In this article, we propose that they can also be used to simplify the joint interpretation of positive predictive value (PPV) and sensitivity estimates across diagnostic accuracy studies of epilepsy data. This is because CSI and GS each provide a single measure that takes the weather forecasting equivalent of PPV and sensitivity into account. We have re‐analysed data from our recent systematic review of diagnostic accuracy studies of administrative epilepsy data using CSI and GS. We summarise the results and benefits of this approach. [ABSTRACT FROM AUTHOR]

The freshwater opossum shrimp Mysis diluviana can undergo extensive diel vertical migration (DVM) to feed in shallow, prey rich strata at night. Bright moonlight limits their night-time migration presumably due to predator avoidance. Using a linked, foraging-bioenergetics model, we evaluated the cost of avoiding predators by simulating the effects of prey density, water temperature, and light intensity on daily feeding and growth of M. diluviana in Lake Pend Oreille, Idaho, USA. We found that when mysid distribution was not limited by moonlight intensity, simulated food consumption (10.3 J day−1) increased 1.6-fold compared to estimated consumption (6.1 J day−1) based on their observed, vertical distribution. Moreover, simulated growth of mysids (0.61 mg day−1) increased 74% compared to that estimated from observed distribution patterns (0.35 mg day−1), when they were located in deeper, darker strata. Given recent insights into partial DVM by M. diluviana, we note that proximate factors associated with predator avoidance in pelagic (light availability) and benthic (hunger level, body size and reproductive status) habitats may convey complimentary benefits to M. diluviana fitness by reducing predation mortality and increasing metabolic efficiency. [ABSTRACT FROM AUTHOR]

The effect of inducers of systemic acquired resistance, dichloroisonicotinic acid (DCINA) and acibenzolar‐S‐methyl (BION), on compatible interactions between Bremia lactucae and lettuce were examined using a detached cotyledon infection assay. Treatment with both activators caused a reduction in sporulation on susceptible cultivars Cobham Green challenged with isolate CL9W and Diana inoculated with isolate Tv, with DCINA being more effective than BION on an equimolar basis. Unexpectedly, treatment with both compounds suppressed the resistance conferred by the Dm7 gene in cv. Diana challenged by isolate CL9W (A7). The frequency of sporulation was greatly increased by DCINA in the incompatible interaction. The suppression of defence was associated with a delay in the onset of the Dm7‐based hypersensitive reaction as indicated by the extended viability of penetrated epidermal cells, and reductions in both the accumulation of the phytoalexin lettucenin A and the deposition of autofluorescent phenolics such as syringaldehyde on plant and oomycete cell walls. The analysis of DCINA homologues indicated that 2‐chloroisonicotinic acid was as effective as the dichloro‐derivative in suppressing resistance in cv. Diana, whereas the absence of the carboxyl group rendered 2,6‐dichloropyridine inactive. Infection of cotyledons by Botrytis cinerea was also found to be enhanced by DCINA treatment. Based on our results, we discuss the possibility that DCINA reduces Dm7 transcription through an epigenetic mechanism, as is supported by bioinformatic analyses of the resistance gene, and that it suppresses jasmonate‐dependent resistance to B. cinerea. [ABSTRACT FROM AUTHOR]

The article discusses arterial gas embolism and decompression sickness, as well as their potential differential diagnosis and recommended treatments. Also cited are a brief history of the conditions including the development of compressor technology for diving in the 1800s, and how decompression sickness was observed by Alphonse Jaminet among construction workers during the construction of the Eads Bridge in St. Louis, Missouri.

We investigate the sensitivity of silicon–oxide–nitride–silicon–oxide (SONOS) charge trapping memory technology to heavy-ion induced single-event effects. Threshold voltage ($V_{T}$) statistics were collected across multiple test chips that contained in total 18 Mb of 40-nm SONOS memory arrays. The arrays were irradiated with Kr and Ar ion beams, and the changes in their $V_{T}$ distributions were analyzed as a function of linear energy transfer (LET), beam fluence, and operating temperature. We observe that heavy ion irradiation induces a tail of disturbed devices in the “program” state distribution, which has also been seen in the response of floating-gate (FG) flash cells. However, the $V_{T}$ distribution of SONOS cells lacks a distinct secondary peak, which is generally attributed to direct ion strikes to the gate-stack of FG cells. This property, combined with the observed change in the $V_{T}$ distribution with LET, suggests that SONOS cells are not particularly sensitive to direct ion strikes but cells in the proximity of an ion’s absorption can still experience a $V_{T}$ shift. These results shed new light on the physical mechanisms underlying the $V_{T}$ shift induced by a single heavy ion in scaled charge trap memory. [ABSTRACT FROM AUTHOR]

One‐hundred seventy‐two households were recruited from regions with high outdoor air pollution (Fresno and Riverside, CA) to participate in a randomized, sham‐controlled, cross‐over study to determine the effectiveness of high‐efficiency air filtration to reduce indoor particle exposures. In 129 households, stand‐alone HEPA air cleaners were placed in a bedroom and in the main living area. In 43 households, high‐efficiency MERV 16 filters were installed in central forced‐air heating and cooling systems and the participating households were asked to run the system on a clean‐air cycle for 15 min per hour. Participating households that completed the study received true air filtration for a year and sham air filtration for a year. Air pollution samples were collected at approximately 6‐month intervals, with two measurements in each of the sham and true filtration periods. One week indoor and outdoor time‐integrated samples were collected for measurement of PM2.5, PM10, and ultrafine particulate matter (UFP) measured as PM0.2. Reflectance measurements were also made on the PM2.5 filters to estimate black carbon. True filtration significantly improved indoor air quality, with a 48% reduction in the geometric mean indoor PM0.2 and PM2.5 concentrations, and a 31% reduction in PM10. Geometric mean concentrations of indoor/outdoor reflectance values, indicating fraction of particles of outdoor origin remaining indoors, decreased by 77%. Improvements in particle concentrations were greater with continuously operating stand‐alone air cleaners than with intermittent central system filtration. Keeping windows closed and increased utilization of the filtration systems further improved indoor air quality. [ABSTRACT FROM AUTHOR]

Firms often make marketing missteps that offend minority consumers. Such missteps are attributed to the lack of diversity within the marketing field. This paper presents a corporate engagement program that partners minority students with a national company as an innovative approach to this problem. Leveraging both passive and active learning, students attend classes and work on original marketing plans for the company. Feedback from both students and the company suggests that both parties learned from each other, adding to the pipeline of future minority marketers while leading to a better understanding of minority consumers. The latter holds promise for the creation of effective communications that resonate with minority consumers. [ABSTRACT FROM AUTHOR]

We evaluate the sensitivity of neuromorphic inference accelerators based on silicon-oxide-nitride-oxide-silicon (SONOS) charge trap memory arrays to total ionizing dose (TID) effects. Data retention statistics were collected for 16 Mbit of 40-nm SONOS digital memory exposed to ionizing radiation from a Co-60 source, showing good retention of the bits up to the maximum dose of 500 krad(Si). Using this data, we formulate a rate-equation-based model for the TID response of trapped charge carriers in the ONO stack and predict the effect of TID on intermediate device states between “program” and “erase.” This model is then used to simulate arrays of low-power, analog SONOS devices that store 8-bit neural network weights and support in situ matrix–vector multiplication. We evaluate the accuracy of the irradiated SONOS-based inference accelerator on two image recognition tasks—CIFAR-10 and the challenging ImageNet data set—using state-of-the-art convolutional neural networks, such as ResNet-50. We find that across the data sets and neural networks evaluated, the accelerator tolerates a maximum TID between 10 and 100 krad(Si), with deeper networks being more susceptible to accuracy losses due to TID. [ABSTRACT FROM AUTHOR]

We evaluate the resilience of CoFeB/MgO/CoFeB magnetic tunnel junctions (MTJs) with perpendicular magnetic anisotropy (PMA) to displacement damage induced by heavy-ion irradiation. MTJs were exposed to 3-MeV Ta2+ ions at different levels of ion beam fluence spanning five orders of magnitude. The devices remained insensitive to beam fluences up to $10^{11}$ ions/cm2, beyond which a gradual degradation in the device magnetoresistance, coercive magnetic field, and spin-transfer-torque (STT) switching voltage were observed, ending with a complete loss of magnetoresistance at very high levels of displacement damage (>0.035 displacements per atom). The loss of magnetoresistance is attributed to structural damage at the MgO interfaces, which allows electrons to scatter among the propagating modes within the tunnel barrier and reduces the net spin polarization. Ion-induced damage to the interface also reduces the PMA. This study clarifies the displacement damage thresholds that lead to significant irreversible changes in the characteristics of STT magnetic random access memory (STT-MRAM) and elucidates the physical mechanisms underlying the deterioration in device properties. [ABSTRACT FROM AUTHOR]

CONTEXT: Hospital policies and culture affect abortion provision. The prevalence and nature of colleague opposition to abortion and how this opposition limits abortion care in U.S. teaching hospitals have not been investigated. METHODS: As part of a mixed‐methods study, a nationwide survey of residency and site directors at 169 accredited obstetrics‐gynecology training programs was conducted in 2015–2016, and 18 in‐depth interviews with program directors were conducted in 2014 and 2017. The prevalence and nature of interprofessional opposition were examined using descriptive statistics, and regional differences were investigated using logistic regression. A modified grounded theoretical approach was used to analyze interview data. RESULTS: Among the 91% of survey respondents who reported that they or their colleagues had wanted or needed to provide abortions in the prior year, 69% faced opposition from colleagues. Most commonly, opposition came from nurses (58%), nursing administration (30%) and anesthesiologists (30%), manifesting as resistance to participating in or cooperating with procedures (51% and 38%, respectively). Fifty‐nine percent of respondents had denied care to patients in the prior year because of colleagues' opposition. Respondents in the Midwest and South were more likely than those in the Northeast to deny abortion care to patients because of such opposition (odds ratios, 3.2 and 4.4, respectively). Interviews revealed how participants had to circumvent opposing colleagues, making abortion provision difficult and leading to delays in and, infrequently, denial of abortion care. CONCLUSIONS: Interprofessional opposition to abortion is widespread in U.S. teaching hospitals. Interventions are needed that prioritize patients' needs while recognizing the challenges hospital colleagues face in their abortion participation decisions. [ABSTRACT FROM AUTHOR]

Analog hardware accelerators, which perform computation within a dense memory array, have the potential to overcome the major bottlenecks faced by digital hardware for data-heavy workloads such as deep learning. Exploiting the intrinsic computational advantages of memory arrays, however, has proven to be challenging principally due to the overhead imposed by the peripheral circuitry and due to the non-ideal properties of memory devices that play the role of the synapse. We review the existing implementations of these accelerators for deep supervised learning, organizing our discussion around the different levels of the accelerator design hierarchy, with an emphasis on circuits and architecture. We explore and consolidate the various approaches that have been proposed to address the critical challenges faced by analog accelerators, for both neural network inference and training, and highlight the key design trade-offs underlying these techniques. [ABSTRACT FROM AUTHOR]

Prostaglandins have been attractive targets in total synthesis for over 50 years, resulting in the development of new synthetic strategies and methodologies that have served the broader chemical community. However, these molecules are not just of academic interest, a number of prostaglandin analogues are used in the clinic, and some are even on the WHO list of essential medicines. In this personal account, we describe our own approach to the family of prostaglandins, which centers around the synthesis of a key enal intermediate, formed from the l‐proline catalysed dimerization of succinaldehyde. We highlight the discovery and further optimization of this key reaction, its scale up, and subsequent application to a range of prostaglandins. [ABSTRACT FROM AUTHOR]

Introduction: The biomedical sciences (BMS) are a central part of the dental curriculum that underpins teaching and clinical practice in all areas of dentistry. Although some specialist groups have proposed curricula in their particular topic areas, there is currently no overarching view of what should be included in a BMS curriculum for undergraduate dental programmes. To address this, the Association for Dental Education in Europe (ADEE) convened a Special Interest Group (SIG) with representatives from across Europe to develop a consensus BMS curriculum for dental programmes. Curriculum: This paper summarises the outcome of the deliberations of this SIG and details a consensus view from the SIG of what a BMS curriculum should include. Conclusions: Given the broad nature of BMS applied to dentistry, this curriculum framework is advisory and seeks to provide programme planners with an indicative list of topics which can be mapped to specific learning objectives within their own curricula. As dentistry becomes increasingly specialised, these will change, or some elements of the undergraduate curriculum may move to the post‐graduate setting. So, this document should be seen as a beginning and it will need regular review as BMS curricula in dentistry evolve. [ABSTRACT FROM AUTHOR]

Our objective was to undertake a systematic review ascertaining the accuracy of using administrative healthcare data to identify epilepsy cases. We searched MEDLINE and Embase from 01/01/1975 to 03/07/2018 for studies evaluating the diagnostic accuracy of routinely collected healthcare data in identifying epilepsy cases. Any disease coding system in use since the International Classification of Diseases, Ninth Revision (ICD‐9) was permissible. Two authors independently screened studies, extracted data, and quality‐assessed studies. We assessed positive predictive value (PPV), sensitivity, negative predictive value (NPV), and specificity. The primary analysis was a narrative synthesis of review findings. Thirty studies were included, published between 1989 and 2018. Risks of bias were low, high, and unclear in 4, 14, and 12 studies, respectively. Coding systems included ICD‐9, ICD‐10, and Read Codes, with or without antiepileptic drugs (AEDs). PPVs included ranges of 5.2%–100% (Canada), 32.7%–96.0% (USA), 47.0%–100% (UK), and 37.0%–88.0% (Norway). Sensitivities included ranges of 22.2%–99.7% (Canada), 12.2%–97.3% (USA), and 79.0%–94.0% (UK). Nineteen studies contained at least one algorithm with a PPV >80%. Sixteen studies contained at least one algorithm with a sensitivity >80%. PPV was highest in algorithms consisting of disease codes (ICD‐10 G40‐41, ICD‐9 345) in combination with one or more AEDs. The addition of symptom codes to this (ICD‐10 R56; ICD‐9 780.3, 780.39) lowered PPV. Sensitivity was highest in algorithms consisting of symptom codes with one or more AEDs. Although using AEDs alone achieved high sensitivities, the associated PPVs were low. Most NPVs and specificities were >90%. We conclude that it is reasonable to use administrative data to identify people with epilepsy (PWE) in epidemiological research. Studies prioritizing high PPVs should focus on combining disease codes with AEDs. Studies prioritizing high sensitivities should focus on combining symptom codes with AEDs. We caution against the use of AEDs alone to identify PWE. [ABSTRACT FROM AUTHOR]

Eye drops are the most common and inexpensive approach to topical ocular drug delivery. Eye drops offer a noninvasive treatment strategy; however, this can be detrimental to therapeutic efficacy when compared to invasive methods such as surgeries, implants, and injections. Improvements to the efficacy of the topical delivery of drugs to ocular tissues are currently being explored and much of this work centers on adjusting the formulation of the eye drops and prolonging the bioavailability of the therapeutic agent. This is often in preference to improving other patient‐focused or clinical factors. In this progress report, conventional, commercially available polymer eye drops are explored and the ability for current and future innovations to maintain the existing benefits of eye drops to the patient is assessed. The final materials and form of the drops (liquid, gel, or other) and the immunological implications for the user are explored. There is currently no consensus for how to most effectively improve the ocular retention and drug delivery capabilities of eye drops, but key issues are highlighted in the context of current methods under development, and potential questions and considerations for future innovations are raised. [ABSTRACT FROM AUTHOR]

Objective: Prior qualitative research with women incarcerated at Rikers Island Jail asked women to anticipate their future contraceptive needs and pregnancy desires upon re-entering the community. We conduct this follow-up study to understand better the actual contraceptive needs and pregnancy desires experienced by women after incarceration.Study Design: We conducted semi-structured in-depth interviews in New York City in 2014 with 10 women incarcerated within the past three years. We coded transcripts using an iterative process, identified emerging themes, and stopped recruitment after reaching thematic saturation.Results: Most participants desired to wait to become pregnant until they had stable housing, income, and employment. A few faced systemic barriers to obtaining contraception, including the process of re-applying for insurance and obtaining medical appointments. For many, incarceration disrupted their use of contraception, insurance status, and relationship with trusted medical providers. Most women lacked trust in the new health professionals they encountered after incarceration.Conclusions: Incarceration disrupted medical care in general, and contraceptive care in particular. Assistance should be provided to re-apply for insurance, make appointments, and support women to see trusted health professionals.Implications: Incarceration further disenfranchises an already marginalized community through disrupting access to medical care and constrains women's reproductive autonomy long after return to the community. [ABSTRACT FROM AUTHOR]

In their article, 'That is not dead which can eternal lie: the aestivation hypothesis for resolving Fermi's paradox', Sandberg et al. try to explain the Fermi paradox (we see no aliens) by claiming that Landauer's principle implies that a civilization can in principle perform far more ( ∼ 10 30 times more) irreversible logical operations (e.g., error-correcting bit erasures) if it conserves its resources until the distant future when the cosmic background temperature is very low. So perhaps aliens are out there, but quietly waiting. Sandberg et al. implicitly assume, however, that computer-generated entropy can only be disposed of by transferring it to the cosmological background. In fact, while this assumption may apply in the distant future, our universe today contains vast reservoirs and other physical systems in non-maximal entropy states, and computer-generated entropy can be transferred to them at the adiabatic conversion rate of one bit of negentropy to erase one bit of error. This can be done at any time, and is not improved by waiting for a low cosmic background temperature. Thus aliens need not wait to be active. As Sandberg et al. do not provide a concrete model of the effect they assert, we construct one and show where their informal argument goes wrong. [ABSTRACT FROM AUTHOR]

Describe the prevalence of considering, wanting, and not obtaining a wanted abortion among a nationally representative sample of 15–44 year olds in the United States who had ever been pregnant. We analyzed data from ever-pregnant respondents (unweighted n = 1789) from a larger online survey about contraceptive access using the nationally representative AmeriSpeak panel. Among those not obtaining wanted abortions, weighted frequencies for sociodemographic characteristics and reasons for not getting the abortion are presented. Nearly 6% of the full sample reported having wanted an abortion they did not obtain. In open-ended responses, respondents most frequently reported individual reasons (43.8%) for not getting an abortion (e.g., changing their mind; personal opposition) and financial, logistical, or informational barriers (24.7%) likely related to policy. A quarter (24.1%) of the sample reported a past abortion. Among those who reported no past abortions, about one-fifth had considered abortion in the past, and 6.8% had wanted or needed one. Among those reporting no prior abortions who had considered abortion, only a third (34.3%) also report ever wanting or needing one. This study begins to quantify the experience, even before the Supreme Court's 2022 decision in Dobbs v. Jackson Women's Health Organization , of being unable to obtain a wanted abortion. Additionally, findings suggest that people in a national sample will answer questions about whether and why they did not obtain a wanted abortion. This study provides the first known national estimates of lifetime history of not getting a wanted abortion. Survey questions can be used for future research. Prospective and ongoing measurement of the inability to get a wanted abortion could be one part of documenting the effects of Dobbs on abortion access. [ABSTRACT FROM AUTHOR]

Rebranding is a widely utilized practice to change the image of a brand in the minds of the consumer through major or minor changes in both its positioning and aesthetics. Yet, evidence suggests it is not meaningfully covered in many marketing classes. This project provides an innovative, engaging, experiential learning opportunity that can be easily adapted for a wide array of marketing classes. Findings indicate the students' knowledge of, familiarity with, and ability to apply rebranding increase as a result of the experience. [ABSTRACT FROM AUTHOR]

Objective: This study describes the perspectives of patients and providers about intrauterine device (IUD) self-removal.Study Design: This qualitative study is a subanalysis of two datasets from a single project, which included semistructured individual interviews with 15 patients and 12 physicians. We derived the data for this analysis from portions of the interviews pertaining to IUD self-removal and provider removal. We analyzed data using deductive and inductive techniques to perform content and thematic analyses.Results: The majority of patients and physicians cited both concerns about and potential benefits of IUD self-removal. Patients cited concerns about safety as the reason they did not wish to remove their own IUD, but physicians did not share these concerns; instead, physicians were apprehensive about not being involved in the discussion to remove the IUD. Both patients and physicians valued having the provider "in the loop" and reported fears about hasty or coerced removal.Conclusions: IUD self-removal is an option that some patients may be interested in. Addressing concerns about safety may make self-removal more appealing to some patients. Addressing physicians' concern about "hasty" removal may require additional training so that providers are better able to support patients' decision making around contraceptive use.Implications: The option of self-removal could have a positive impact on reproductive autonomy and patient decision making. [ABSTRACT FROM AUTHOR]

Abstract: Prevalence of diabetes and obesity in Mexican Pima Indians is low, while prevalence in US Pima Indians is high. Although lifestyle likely accounts for much of the difference, the role of genetic factors is not well explored. To examine this, we genotyped 359 single nucleotide polymorphisms, including established type 2 diabetes and obesity variants from genome‐wide association studies (GWAS) and 96 random markers, in 342 Mexican Pimas. A multimarker risk score of obesity variants was associated with body mass index (BMI; β = 0.81 kg/m2 per SD, P = 0.0066). The mean value of the score was lower in Mexican Pimas than in US Pimas (P = 4.3 × 10−11), and differences in allele frequencies at established loci could account for approximately 7% of the population difference in BMI; however, the difference in risk scores was consistent with evolutionary neutrality given genetic distance. To identify loci potentially under recent natural selection, allele frequencies at 283 variants were compared between US and Mexican Pimas, accounting for genetic distance. The largest differences were seen at HLA markers (e.g., rs9271720, difference = 0.75, P = 8.7 × 10–9); genetic distances at HLA were greater than at random markers (P = 1.6 × 10–46). Analyses of GWAS data in 937 US Pimas also showed sharing of alleles identical by descent at HLA that exceeds its genomic expectation (P = 7.0 × 10–10). These results suggest that, in addition to the widely recognized balancing selection at HLA, recent directional selection may also occur, resulting in marked allelic differentiation between closely related populations. [ABSTRACT FROM AUTHOR]

A new model to explore negative remanent magnetization is presented. Recently, a model for magnetic materials that have wasp-waist hysteresis loops was applied to a homogeneous thin film. This model postulated two interacting antiferromagnetically coupled media: one medium with low moment and relatively high coercivity, and one medium with a relatively high moment and low coercivity. This model is applicable to the situation where the "width" of the loop near zero is "negative." The major loop of such a material crosses itself, leading to negative remanent magnetization. The present paper introduces a new concept of a need for a third dimension to add to the usual magnetization versus applied field graph, demonstrates that there is no crossing, and discusses the nature of the losses in these materials. [ABSTRACT FROM AUTHOR]

Evidence has recently been given for the Bose-Einstein condensation (BEC) of magnons in nanostructures. This behavior occurs for nanoparticles some tens of nanometers in size (having some millions of atoms in a nanoparticle). Here we explore the effect of particle size on the BEC critical temperature and the blocking temperature. These considerations lead to a proposed phase diagram for magnetic behavior in nanoparticles, with distinct BEC, superparamagnetic, and ferromagnetic phases. [ABSTRACT FROM AUTHOR]

Neuronal connections form the physical basis for communication in the brain. Recently, there has been much interest in mapping the “connectome” to understand how brain structure gives rise to brain function, and ultimately, to behaviour. These attempts to map the connectome have largely assumed that connections are stable once formed. Recent studies, however, indicate that connections in mammalian brains may undergo rewiring during learning and experience-dependent plasticity. This suggests that the connectome is more dynamic than previously thought. To what extent can neural circuitry be rewired in the healthy adult brain? The connectome has been subdivided into multiple levels of scale, from synapses and microcircuits through to long-range tracts. Here, we examine the evidence for rewiring at each level. We then consider the role played by rewiring during learning. We conclude that harnessing rewiring offers new avenues to treat brain diseases. [ABSTRACT FROM AUTHOR]

Gene expression in a tissue-specific context depends on the combined efforts of epigenetic, transcriptional and post-transcriptional processes that lead to the production of specific proteins that are important determinants of cellular identity. Ribosomes are a central component of the protein biosynthesis machinery in cells; however, their regulatory roles in the translational control of gene expression in skeletal muscle remain to be defined. In a genetic screen to identify critical regulators of myogenesis, we identified a DEAD-Box RNA helicase, DDX27, that is required for skeletal muscle growth and regeneration. We demonstrate that DDX27 regulates ribosomal RNA (rRNA) maturation, and thereby the ribosome biogenesis and the translation of specific transcripts during myogenesis. These findings provide insight into the translational regulation of gene expression in myogenesis and suggest novel functions for ribosomes in regulating gene expression in skeletal muscles. [ABSTRACT FROM AUTHOR]

It is well known that the energy barrier for magnetization reversal, EB, varies quadratically with the magnetic field for the Stoner-Wohlfarth model. However, the enthalpy H (switching energy) required to reverse the magnetization is the sum of EB and the work Wf done by the Néel fluctuation field. The sum of these two terms gives an enthalpy of reversal. If the fluctuation field is uniaxial and parallel to the holding field, then the enthalpy barrier for switching is linear in the holding field. The linearity is consistent with certain experimental results. If the fluctuation field is anisotropic, then for the same size field, the probability of the particle’s switching will depend upon the direction of that field. The paper discusses the holding field variation of the energy barrier for different fluctuation field directions. [ABSTRACT FROM AUTHOR]

Objective The objective of the present study was to determine the effects of concurrent LPS and cytokine priming, reflective of the in vivo milieu, on macrophage production of key periodontitis associated cytokines TNF, IL-1β and IL-6. Design THP-1 cells were pre-treated with combinations of Porphyromonas gingivalis and Escherichia coli lipopolysaccharide (LPS), concurrently with polarising cytokines IFNγ and IL-4, or PMA as a non-polarised control. Production of key periodontitis associated cytokines in response to subsequent LPS challenge were measured by enzyme − linked immunosorbent assay. Results Compared with cells incubated with IFNγ or IL-4 alone in the “polarisation” phase, macrophages that were incubated with LPS during the first 24 h displayed a down-regulation of TNF and IL-1β production upon secondary LPS treatment in the “activation” phase. In all three macrophage populations (M0, M1 and M2), pre-treatment with P. gingivalis LPS during the polarisation process led to a significant decrease in TNF production in response to subsequent activation by LPS (p = 0.007, p = 0.002 and p = 0.004, respectively). Pre-treatment with E. coli LPS also led to a significant down-regulation in TNF production in all three macrophage populations (p < 0.001). Furthermore, the presence of E. coli LPS during polarisation also led to the down-regulation of IL-1β in the M1 population (p < 0.001), whereas there was no measurable effect on IL-1β production in M0 or M2 macrophages. There was no significant effect on IL-6 production. Conclusions Macrophages become refractory to further LPS challenge, whereby production of key periodontitis associated cytokines TNF and IL-1β is reduced after exposure to LPS during the polarisation phase, even in the presence of inflammatory polarising cytokines. This diminished cytokine response may lead to the reduced ability to clear infection and transition to chronic inflammation seen in periodontitis. [ABSTRACT FROM AUTHOR]

Objective: This study describes the perceptions and experiences of family physicians when women request early intrauterine device (IUD) removal.Study Design: This qualitative study included semistructured individual interviews with 12 physicians who encountered patients seeking early IUD removal. We identified eligible participants via chart review. We analyzed interviews using deductive and inductive techniques to identify content and themes.Results: Physicians consistently referred to IUDs as the "best" or their "favorite" method, and several joked that they tried to "sell" the IUD during contraceptive counseling. Most reported having mixed or negative feelings when patients opted to remove the IUD. Most encouraged their patients to continue the IUD, hoping to delay removal until symptoms resolved so that removal was not needed. Some physicians reported feeling guilty or as if they had "failed" when a patient wanted the IUD removed. Many providers reported a conflict between valuing patient autonomy and feeling that early removal was not in the patient's best interest.Conclusions: Physicians have complex and contradictory feelings about early IUD removal. While most providers acknowledged the need for patient autonomy, they still reported encouraging IUD continuation based on their own opinion about the IUD.Implications: While IUDs are highly effective and well-liked contraceptives, providers' responses to IUD removal requests have implications for both reproductive autonomy as well as the doctor-patient relationship. More work is needed to ensure that providers remove a patient's IUD when requested. [ABSTRACT FROM AUTHOR]

Wasp-waist and pot-belly hysteresis loops have been observed in many materials. When only the major loop is reported, the results are insufficient to establish which processes are involved. We present two models for wasp-waist materials that produce virtually indistinguishable major loops, but show that first-order reversal curves can be used to separate the effects. In the simplest model, we take a soft magnetic material and a hard material and exchange couple them. When the exchange is positive, the loop is conventional. However, for negative (antiferromagnetic) exchange, the wasp-waist loop is obtained. Negative coupling of two materials with different switching field distributions leads to pot-bellied loops. [ABSTRACT FROM AUTHOR]

Bimodal magnetic behavior has been observed in a (0.3-nm Co/1.2-nm Pt)[SUB15] multilayer film. In that) film, the Kerr rotation and ellipticity exhibit magneto-optic hysteresis loops with two distinct field-dependent steps, so that there are four stable magnetization states. The magnetic aftereffects of the two distinct types of decay at the two sets of holding fields have been analyzed. Thus, it is possible to measure and calculate the two types of decay individually. We show that the shift in log time of the aftereffect curves for both the sets are linear. The fluctuation fields for the two states are calculated using these methods. We also confirm experimentally the conjecture of the Preisach-Arrhenius model that the shape of the aftereffect curve is the same as the major hysteresis curve. This helps in finding the chemical potential. [ABSTRACT FROM AUTHOR]

The temperature variation of the magnetic relaxation process obtained from dc magnetization measurements are investigated in fine Fe[sub 3]O[sub 4] powder in the temperature range of 5 K

Magneto-optical Kerr effect measurements performed on (0.3 nm Co/x Pt)[sub 15] multilayers with x=0.3–2.0 nm showed all samples to exhibit strong perpendicular magnetic anisotropy. Recent work has shown that for compositions near (0.3 nm Co/1.2 nm Pt)[sub 15], both polar Kerr rotation and ellipticity exhibit bimodal reversals in which the major hysteresis loops have two distinct field-dependent steps due to the contributions of two magnetic phases. To better understand this bimodal magnetization phenomenon, Kerr rotation and ellipticity were determined as a function of radial position from the center to the edge of this disk sample. These measurements exhibit a continuous variation from two-step (bimodal) behavior in the center to single-step (unimodal) behavior at the edge. Since these films were deposited via MBE with a heated substrate, it is believed that this phenomenon is related to thermally induced variations in interface effects such as alloying, abruptness, and morphology. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Unique properties of the Zr[sub 3](Rh[sub (1-x)]Pd[sub x])[sub 4] alloy system are reported here. Contrary to most metallically bonded systems which are not quick to change magnetic behavior with alloy concentration, this system does. Pure Zr[sub 3]Rh[sub 4] and pure Zr[sub 3]Pd[sub 4] are each nonmagnetic, while in the limited range 0.02

Focuses on a magnetic aftereffect study of the reversal behavior in a bimodal magneto-optical medium with perpendicular magnetic anisotropy. Experimental procedure; Results and discussion; Conclusion.

Presents information on a study which investigated the magnetization reversal and magneto-optical images of cobalt/platinum multilayer films using Kerr microscopy. Bimodal features; Magnetic images of the multilayer film.

Aim: There is no shortage of information on the potential consequences of consuming mephedrone. However, these assessments relate primarily to the physical and psychological effects of the drug. Less attention is paid to the social harms to the user or broader society. The aim of this paper is to investigate the physical, psychological and social harms and benefits of mephedrone use as perceived by users and practitioners.Methods: The findings reported here are based on: (1) semi-structured interviews with 12 mephedrone users and (2) semi-structured interviews with 20 practitioners.Findings: The most common perceived benefits of mephedrone consumption were the intensity of the “high”, feelings of happiness, enhanced confidence and its ability to suppress negative feelings associated with a range of problems. Its social benefits mainly concerned enhancing social skills (e.g. enabling conversation) and helping to make friends. The most frequently mentioned harms were physical disorders, such as the negative effects of snorting on nose tissues and injecting on the skin and veins, as well as psychological harms, such as depression, paranoia, hallucinations and sleep disorders. The main social problems were the effects of mephedrone use on family life, employment, finances and involvement in acquisitive and violent crime.Conclusions: Future research should continue to explore the full range of positive and negative effects of mephedrone use on users and those close to them to establish a solid evidence base from which to inform treatment and prevention. [ABSTRACT FROM PUBLISHER]

The paper describes investigation of ferromagnetism at low temperatures. We explored the magneto-optical properties, influenced by photon–magnon interactions, of a ferromagnetic Co/Pd multilayered thin film below and above the magnon Bose–Einstein Condensation (BEC) temperature. Analyses of SQUID and MOKE low temperature experimental results reveal a noticeable phase transition in both magnetic and magneto-optical properties of the material at the BEC temperature. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study is to describe the thoughts and experiences of women who report discussing intrauterine device (IUD) removal within 9 months of insertion.Study Design: This is a qualitative study, consisting of semistructured individual interviews with 16 women who considered early elective IUD removal. We identified eligible participants via chart review. We analyzed interviews using a modified grounded theory approach.Results: While pain and bleeding were prominent reasons for removal, women also discussed many other symptoms and concerns. Most women reported a strong desire to have a successful IUD experience, and all reported waiting for symptoms to resolve prior to their visit. Some women reported that providers supported their choice, while others reported that providers preferred that they continue the IUD despite symptoms and concerns. Some women reported providers' resistance or refusal to remove the IUDs. The women who reported that their providers were neutral about IUD removal more frequently expressed satisfaction with the visit. When the provider resisted removal, women felt frustrated, even as they acknowledged their doctor's good intentions. In several cases, this may have hurt the doctor-patient relationship.Conclusions: When physicians resist early elective IUD removal, it may impact patient satisfaction and even jeopardize the doctor-patient relationship.Implications: Though IUDs are highly effective and well-liked contraceptives, some patients choose to discontinue the method. Because provision of patient-centered contraceptive care includes IUD removal when requested, providers must ensure that their counseling is unbiased and that they do not place perceived or real barriers to IUD removal. [ABSTRACT FROM AUTHOR]

Investigates the basic properties of the proposed Preisach accommodation properties of recording media on a commercial flexible disk material. Accommodation in Preisach models; Experimental analysis of accommodation in recording media.

Presents a study of the magnetization process of granular cobalt-silver films. Use of the magneto-optical indicator film technique and magnetic force microscopy in the study; Quality characterization of high-temperature superconductors; Analysis of magnetization domains.

Presents a study that investigated artifacts in magnetic resonance imaging (MRI) from metals. Importance of magnetic properties of clips or other surgical materials placed in the human body; Information on the artifacts produced by MRI by material magnetic susceptibility; Description of the nuclear MRI facility.

Examines the effect of nitrogen on the magnetic properties of hard magnets using the Wigner-Seitz construct. Background on the Wigner-Seitz cell; List of magnet materials which were found to have enhanced magnetism upon nitriding; Analysis of the results for αiron.

Presents a study which investigated the long-time magnetic relaxation measurements on a quench melt grown YBCO superconductor. Experimental methods; Results and discussion.

Focuses on a study which presented Monte Carlo simulations of the magnetocaloric effect in superferromagnetic clusters having uniaxial magnetic anisotropy. Background on magnetocaloric effect; Calculations and results; Conclusion.