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Skull growth involves the expansion of both the flat calvarial bones of the skull and the fibrous marginal zones, termed sutures, between them. This process depends on co‐ordinated proliferation of mesenchymal‐derived progenitor cells within the sutures, and their differentiation to osteoblasts which produce the bone matrix required to expand the size of the bony plates. Defects lead to premature closure of these sutures, termed craniosynostosis, resulting in heterogeneous head shape differences due to restricted growth of one or more sutures. The impact on the individual depends on how many and which sutures are affected and the severity of the effect. Several genetic loci are responsible, including a wide range of variants in the gene for the interleukin 11 receptor (IL11RA, OMIM#600939). Recent work from Kespohl and colleagues provides new insights into how some of these variants influence IL‐11R function; we discuss their influences on IL‐11R structure and IL‐11 function as a stimulus of osteoblast differentiation. [ABSTRACT FROM AUTHOR]

Hypertension is a widely prevalent disease and uncontrolled hypertension predisposes affected individuals to severe adverse effects. Though the importance of controlling hypertension is clear, the multitude of therapeutic regimens and patient factors that affect the success of blood pressure control makes it difficult to predict the likelihood to predict whether a patient's blood pressure will be controlled. This project endeavors to investigate whether machine learning can accurately predict the control of a patient's hypertension within 12 months of a clinical encounter. To build the machine learning model, a retrospective review of the electronic medical records of 350,008 patients 18 years of age and older between January 1, 2015 and June 1, 2022 was performed to form model training and testing cohorts. The data included in the model included medication combinations, patient laboratory values, vital sign measurements, comorbidities, healthcare encounters, and demographic information. The mean age of the patient population was 65.6 years with 161,283 (46.1%) men and 275,001 (78.6%) white. A sliding time window of data was used to both prohibit data leakage from training sets to test sets and to maximize model performance. This sliding window resulted in using the study data to create 287 predictive models each using 2 years of training data and one week of testing data for a total study duration of five and a half years. Model performance was combined across all models. The primary outcome, prediction of blood pressure control within 12 months demonstrated an area under the curve of 0.76 (95% confidence interval; 0.75–0.76), sensitivity of 61.52% (61.0–62.03%), specificity of 75.69% (75.25–76.13%), positive predictive value of 67.75% (67.51–67.99%), and negative predictive value of 70.49% (70.32–70.66%). An AUC of 0.756 is considered to be moderately good for machine learning models. While the accuracy of this model is promising, it is impossible to state with certainty the clinical relevancy of any clinical support ML model without deploying it in a clinical setting and studying its impact on health outcomes. By also incorporating uncertainty analysis for every prediction, the authors believe that this approach offers the best-known solution to predicting hypertension control and that machine learning may be able to improve the accuracy of hypertension control predictions using patient information already available in the electronic health record. This method can serve as a foundation with further research to strengthen the model accuracy and to help determine clinical relevance. [ABSTRACT FROM AUTHOR]

Infections caused by malaria parasites place an enormous burden on the world's poorest communities. Breakthrough drugs with novel mechanisms of action are urgently needed. As an organism that undergoes rapid growth and division, the malaria parasite Plasmodium falciparum is highly reliant on protein synthesis, which in turn requires aminoacyl-tRNA synthetases (aaRSs) to charge tRNAs with their corresponding amino acid. Protein translation is required at all stages of the parasite life cycle; thus, aaRS inhibitors have the potential for whole-of-life-cycle antimalarial activity. This review focuses on efforts to identify potent plasmodium-specific aaRS inhibitors using phenotypic screening, target validation, and structure-guided drug design. Recent work reveals that aaRSs are susceptible targets for a class of AMP-mimicking nucleoside sulfamates that target the enzymes via a novel reaction hijacking mechanism. This finding opens up the possibility of generating bespoke inhibitors of different aaRSs, providing new drug leads. [ABSTRACT FROM AUTHOR]

Recent work of Griffin, Ono, Rolen, and Zagier shows that the Jensen polynomials for the Riemann xi function converge to the Hermite polynomials under a suitable normalization. We generalize this result, proving that the normalized Jensen polynomials for a large class of genus zero or one entire functions converge either to the Hermite polynomials, or to a class of polynomials which can be written as a confluent hypergeometric function. [ABSTRACT FROM AUTHOR]

The classical AGM produces wonderful infinite sequences of arithmetic and geometric means with common limit. For finite fields F q , with q ≡ 3 (mod 4) , we introduce a finite field analogue AGM F q that spawns directed finite graphs instead of infinite sequences. The compilation of these graphs reminds one of a jellyfish swarm, as the 3D renderings of the connected components resemble jellyfish (i.e., tentacles connected to a bell head). These swarms turn out to be more than the stuff of child's play; they are taxonomical devices in number theory. Each jellyfish is an isogeny graph of elliptic curves with isomorphic groups of F q -points, which can be used to prove that each swarm has at least (1 / 2 − ε) q jellyfish. This interpretation also gives a description of the class numbers of Gauss, Hurwitz, and Kronecker which is akin to counting types of spots on jellyfish. [ABSTRACT FROM AUTHOR]

In the wake of the era of Trump and Brexit, legacies and values of European Enlightenment seem under threat as never before. Cosmopolitanism in particular, generally understood as an Enlightenment virtue, has come to be associated with a sort of rootlessness, and has not, as generally understood, valued local affiliation. For David Goodhart, writing in 2017, this characteristic has resulted in a polarisation between "anywheres" (liberal middleclass cosmopolitans) and "somewheres" (broadly speaking, conservative working-class voters who have strong attachments to their nation and places of origin). An Irish Tory monarchist who sought in his poem The Deserted Village (1770) to defend rural communities from the ravages of economic modernity, Oliver Goldsmith (1728-74) was also in other key works a cosmopolitan commentator who compared countries in order to warn Britain against the dangers of economic liberalism, as he did in The Traveller, or a Prospect of Society (1764). Thus, he could be thought of as a more conservative cosmopolitan than many of his British and French peers; as such his particular enlightenment legacy is his example of a middle ground between the "anywheres" and "somewheres" of Goodhart's thesis. [ABSTRACT FROM AUTHOR]

We explicitly construct the Dirichlet series $$\begin{equation*}L_{\mathrm{Tam}}(s):=\sum_{m=1}^{\infty}\frac{P_{\mathrm{Tam}}(m)}{m^s},\end{equation*}$$ where |$P_{\mathrm{Tam}}(m)$| is the proportion of elliptic curves |$E/\mathbb{Q}$| in short Weierstrass form with Tamagawa product m. Although there are no |$E/\mathbb{Q}$| with everywhere good reduction, we prove that the proportion with trivial Tamagawa product is |$P_{\mathrm{Tam}}(1)={0.5053\dots}$|⁠. As a corollary, we find that |$L_{\mathrm{Tam}}(-1)={1.8193\dots}$| is the average Tamagawa product for elliptic curves over |$\mathbb{Q}$|⁠. We give an application of these results to canonical and Weil heights. [ABSTRACT FROM AUTHOR]

In this note we obtain effective lower bounds for the canonical heights of non-torsion points on E(Q) by making use of suitable elliptic curve ideal class pairings ΨE,−D : E(Q) × E−D(Q) &#8594 CL(−D). In terms of the class number H(−D) and TE(−D), a logarithmic function in D, we prove h(P) > |Etor(Q)|2/(H(−D)+ |Etor(Q)|)2 ⋅ TE(−D). [ABSTRACT FROM AUTHOR]

For positive rank r elliptic curves E (Q) , we employ ideal class pairings E (Q) × E − D (Q) → CL (− D) , for quadratic twists E − D (Q) with a suitable "small y -height" rational point, to obtain explicit class number lower bounds that improve on earlier work by the authors. For the curves E (a) : y 2 = x 3 − a , with rank r (a) , this gives h (− D) ≥ 1 10 ⋅ | E tor (Q) | R Q (E) ⋅ π r (a) 2 2 r (a) Γ (r (a) 2 + 1) ⋅ log ⁡ (D) r (a) 2 log ⁡ log ⁡ D , representing a general improvement to the classical lower bound of Goldfeld, Gross and Zagier when r (a) ≥ 3. We prove that the number of twists E − D (a) (Q) with such a suitable point (resp. with such a point and rank ≥2 under the Parity Conjecture) is ≫ a , ε X 1 2 − ε. We give infinitely many cases where r (a) ≥ 6. These results can be viewed as an analogue of the classical estimate of Gouvêa and Mazur for the number of rank ≥2 quadratic twists, where in addition we obtain "log-power" improvements to the Goldfeld-Gross-Zagier class number lower bound. [ABSTRACT FROM AUTHOR]

Background: People with aphasia have been engaging with research in a variety of ways. There are few descriptions of how they are involved in participatory research methodologies and even fewer reports describe their perspective on participating as co-researchers. Aims: To explore the experiences and reflections of two people with aphasia, BG and MG, on being involved in participatory research studies as co-researchers – the Conversation Partner Programme Evaluation Project and the Friendship and Aphasia Project. Methods: Semi-structured interviews were conducted with two people with aphasia about their experiences of engaging in participatory research as co-researchers. Data were analysed thematically. Outcomes & Results: Retrospective reflection by MG and BG resulted in five interlinked themes: Involvement in participatory research processes: “More than a guinea pig” Group process: “It’s us not them … completely different” Flexibility and creativity: new ways to co-generate and co-analyse data Personal transformations and transformative actions arising from the research: “The tortoise wants to be like the hare again” Enhancing quality and meaningfulness: “You get more things out of it for more people” Involvement in participatory research processes: “More than a guinea pig” Group process: “It’s us not them … completely different” Flexibility and creativity: new ways to co-generate and co-analyse dataPersonal transformations and transformative actions arising from the research: “The tortoise wants to be like the hare again” Enhancing quality and meaningfulness: “You get more things out of it for more people” Conclusions: Participatory research methodologies encourage and support non-traditional methods and boundary crossing relationships between academic researchers and people with aphasia. MG and BG’s reflections and recommendations suggest possibilities for enhancing collaboration and equality within our research practices. [ABSTRACT FROM AUTHOR]

Modular and mock modular forms possess many striking p-adic properties, as studied by Bringmann, Guerzhoy, Kane, Kent, Ono, and others. Candelori developed a geometric theory of harmonic Maass forms arising from the de Rham cohomology of modular curves. In the setting of over-convergent p-adic modular forms, Candelori and Castella showed this leads to p-adic analogs of harmonic Maass forms. In this paper we take an analytic approach to construct p-adic analogs of harmonic Maass forms of weight 0 with square free level. Although our approaches differ, where the two theories intersect the forms constructed are the same. However our analytic construction defines these functions on the full super-singular locus as well as on the ordinary locus. As with classical harmonic Maass forms, these p-adic analogs are connected to weight 2 cusp forms and their modular derivatives are weight 2 weakly holomorphic modular forms. Traces of their CM values also interpolate the coefficients of half-integer weight modular and mock modular forms. We demonstrate this through the construction of p-adic analogs of two families of theta lifts for these forms. [ABSTRACT FROM AUTHOR]

Ideal class pairings map the rational points of rank r ≥ 1 elliptic curves E / Q to the ideal class groups CL (− D) of certain imaginary quadratic fields. These pairings imply that h (− D) ≥ 1 2 (c (E) − ε) (log ⁡ D) r 2 for sufficiently large discriminants − D in certain families, where c (E) is a natural constant. These bounds are effective, and they offer improvements to known lower bounds for many discriminants. [ABSTRACT FROM AUTHOR]

The article discusses the Spanish source of Oliver Goldsmith's 1759 poem "On a Beautiful Youth Struck Blind With Lightning," particularly his two quatrains. Also cited are an analysis by editor Roger Lonsdale of Goldsmith's poetry in which he found that a version of the quatrain appeared in a 1760 issue of the "British Magazine," as well as the studies by Peter Cunningham, Austin Dobson, and Arthur Friedman on Goldsmith's work.

Pancreatic cancer has one of the poorest prognoses of all malignancies, with little improvement in clinical outcome over the past 40 years. Pancreatic ductal adenocarcinoma is responsible for the vast majority of pancreatic cancer cases, and is characterised by the presence of a dense stroma that impacts therapeutic efficacy and drives pro-tumorigenic programs. More specifically, the inflammatory nature of the tumour microenvironment is thought to underlie the loss of anti-tumour immunity and development of resistance to current treatments. Inflammatory pathways are largely mediated by the expression of, and signalling through, cytokines, chemokines, and other cellular messengers. In recent years, there has been much attention focused on dual targeting of cancer cells and the tumour microenvironment. Here we review our current understanding of the role of IL-6, and the broader IL-6 cytokine family, in pancreatic cancer, including their contribution to pancreatic inflammation and various roles in pancreatic cancer pathogenesis. We also summarise potential opportunities for therapeutic targeting of these pathways as an avenue towards combating poor patient outcomes. [ABSTRACT FROM AUTHOR]

The article focuses on Professor Sir Richard Rustom Kharsedji Sorabji which is is one of the foremost philosophers and scholars of philosophy active in the world and over the past century. It mentions Sorabji has also carved out a scholarly field in English, namely the study of the late antique commentators on Aristotle. It also mentions insightful and empathetic interlocutor on topics ranging well beyond ancient Greek philosophy.

Atherothrombosis leads to complications of myocardial infarction and stroke as a result of shear-induced platelet aggregation (SIPA). Clinicians and researchers may benefit from diagnostic and benchtop microfluidic assays that assess the thrombotic activity of an individual. Currently, there are several different proposed point-of-care diagnostics and microfluidic thrombosis assays with different design parameters and end points. The microfluidic geometry, surface coatings, and anticoagulation may strongly influence the precision of these assays. Variability in selected end points also persists, leading to ambiguous results. This study aims to assess the effects of three physiologically relevant extrinsic design factors on the variability of a single end point to provide a quantified rationale for design parameter and end-point standardization. Using a design of experiments approach, we show that the methods of channel fabrication and collagen surface coating significantly impact the variability of occlusion time from porcine whole blood, while anticoagulant selection between heparin and citrate did not significantly impact the variability. No factor was determined to significantly impact the mean occlusion time within the assay. Occlusive thrombus was found to consistently form in the first third (333 μm) of the high shear zone and not in the shear gradient regions. The selection of these factors in the design of point-of-care diagnostics and experimental SIPA assays may lead to increased precision and specificity in high shear thrombosis studies. [ABSTRACT FROM AUTHOR]

The article discusses the response on Melvyn New's review of book "The Letters of Oliver Goldsmith." It mentions review is seeking a popular audience, and, somewhat peculiarly, not paying enough attention to Laurence Sterne and statement is untrue, as is its implication of plagiarism. It also mentions Katharine Balderston's pioneering work is freely and repeatedly acknowledged and seek to map the Irish Enlightenment.

In 1927, Pólya proved that the Riemann hypothesis is equivalent to the hyperbolicity of Jensen polynomials for the Riemann zeta function ζ(s) at its point of symmetry. This hyperbolicity has been proved for degrees d ≥3. We obtain an asymptotic formula for the central derivatives ζ(2n)(1=2) that is accurate to all orders, which allows us to prove the hyperbolicity of all but finitely many of the Jensen polynomials of each degree. Moreover, we establish hyperbolicity for all d ≥8. These results follow from a general theorem which models such polynomials by Hermite polynomials. In the case of the Riemann zeta function, this proves the Gaussian unitary ensemble random matrix model prediction in derivative aspect. The general theorem also allows us to prove a conjecture of Chen, Jia, and Wang on the partition function. [ABSTRACT FROM AUTHOR]

• Phosphonic acids were deposited onto four different platinum catalyst supports. • Deposited modifiers provide Brønsted acid sites, creating an acid-metal catalyst. • The strength of Brønsted acid sites is dependent on the modifier tail functionality. • On supports with weak or no Brønsted acidity, modifiers enhance deoxygenation. • On strongly acidic supports, modification leads to a loss of deoxygenation activity. Bifunctional catalysts comprised of both noble metal and Brønsted acid sites are of growing interest for many reactions, such as the hydrodeoxygenation (HDO) of oxygenates produced by the deconstruction of lignocellulosic biomass. One method of preparing a bifunctional metal-acid catalyst is to modify the supporting material of a metal catalyst with acid-containing ligands, such as phosphonic acids (PAs), which provide tunable Brønsted acid sites at the metal-support interface. Here, we explore the potential for PA modification to improve HDO rates on Al 2 O 3 , TiO 2 , CeO 2 , and SiO 2 -Al 2 O 3 supports. PAs containing either alkyl or carboxylic acid (CA) tails were used to modify Pt catalysts on each support. PA modification improved HDO rates for the model compound benzyl alcohol when applied to Pt supported by Al 2 O 3 , TiO 2 , and CeO 2 , but had a negative effect on the HDO rate of Pt/SiO 2 -Al 2 O 3. Measurements of the relative strength of Brønsted acid sites present on the modified and unmodified catalysts suggested that PAs improved HDO when they provided new or stronger Brønsted acid sites. Additionally, the strength of the Brønsted acid sites provided by PA modifiers were tunable by altering the tail functionality, which affected the rates of HDO. These results suggest that PAs can be used to modify a variety of supports to prepare bifunctional acid-metal catalysts. [ABSTRACT FROM AUTHOR]

Seat effective amplitude transmissibilities (SEAT values) quantify the influence of seats on discomfort caused by vibration. This study investigated SEAT values with vertical mechanical shocks at low, medium, and high magnitudes (0.5, 1.0, and 2.0 ms-1.75) at frequencies between 1.0 and 16 Hz. With 18 subjects sitting on a rigid seat and two foam cushions, SEAT values were measured objectively (from the transmitted vibration), measured subjectively (by the responses of subjects), and predicted (using a model of the seat-passenger system). Except with high magnitude low frequency shocks, predicted SEAT values were similar to measured SEAT values. With shocks causing subjects to rise off a cushion and subsequently impact the cushion (low frequencies around 1 g), subjective SEAT values were better estimated using predicted SEAT values than objectively measured SEAT values, because accelerometers on cushions exaggerated the impact of the falling subject. However, accelerometers on rigid seats will underestimate such impacts. [ABSTRACT FROM AUTHOR]

The author comments on the article "The Influence-Network Model of the Photojournalistic Icon" by Nicole Dahmen, Natalia Mielczarek and David D. Perlmutter, that was published within the issue, with topics that include photojournalism, iconic photographs, and digital media

Source Citation: Major Extremity Trauma Research Consortium (METRC); O'Toole RV, Stein DM, O'Hara NN, et al. Aspirin or low-molecular-weight heparin for thromboprophylaxis after a fracture. N Engl J Med. 2023;388:203-213. 36652352 Clinical Impact Ratings: Hospitalists: GIM/FP/GP: Hematology: [ABSTRACT FROM AUTHOR]

Platelet accumulation under high shear rates at the site of atherosclerotic plaque rupture leads to myocardial infarction and stroke. Current antiplatelet therapies remain ineffective within a large percentage of the population, while presenting significant risks for bleeding. We explore a novel way to inhibit arterial thrombus formation by biophysical means without the use of platelet inactivating drugs. Our computational multi-scale dynamics model has predicted that charged particles of a specific size may entangle von Willebrand Factor (vWF) polymers and reduce the amount of elongation at high shear rates. We tested this hypothesis experimentally for negatively charged nanoparticles (CNP) to inhibit arterial thrombus formation. CNP of a particular size and charge inhibited thrombus formation, with a 10-fold peak inhibition over control conditions of thrombotic occlusion. Particles of differing material composition, size, and charge had little effect as predicted by computational studies. Surprisingly, the dose response curve was not sigmoidal, but exhibited a peak at 1.5 CNP:vWF proteins, which was not predicted by the model. This study describes a new antithrombotic agent that may have a different mechanism of action than current pharmaceutical therapies. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various topics in the issue including role of Mary Shelley's novel "Frankenstein" as first fictional response to climate change; Frankenstein's relationship to ethical reproductive science; and the novel "Frankenstein in Baghdad."

Background: Thermotactile thresholds and vibrotactile thresholds are measured to assist the diagnosis of the sensorineural component of the hand-arm vibration syndrome (HAVS). Objectives: This study investigates whether thermotactile and vibrotactile thresholds distinguish between fingers with and without numbness and tingling. Methods: In 60 males reporting symptoms of the hand-arm vibration syndrome, thermotactile thresholds for detecting hot and cold temperatures and vibrotactile thresholds at 31.5 and 125 Hz were measured on the index and little fingers of both hands. Results: In fingers reported to suffer numbness or tingling, hot thresholds increased, cold thresholds decreased, and vibrotactile thresholds at both 31.5 and 125 Hz increased. With sensorineural symptoms on all three phalanges (i.e. numbness or tingling scores of 6), both thermotactile thresholds and both vibrotactile thresholds had sensitivities greater than 80% and specificities around 90%, with areas under the receiver operating characteristic curves around 0.9. There were correlations between all four thresholds, but cold thresholds had greater sensitivity and greater specificity on fingers with numbness or tingling on only the distal phalanx (i.e. numbness or tingling scores of 1) suggesting cold thresholds provide better indications of early sensorineural disorder. Conclusions: Thermotactile thresholds and vibrotactile thresholds can provide useful indications of sensorineural function in patients reporting symptoms of the sensorineural component of HAVS. [ABSTRACT FROM AUTHOR]

Purpose: This study investigates the effects of room temperature on two standard tests used to assist the diagnosis of vibration-induced white finger (VWF): finger rewarming times and finger systolic blood pressures. Methods: Twelve healthy males and twelve healthy females participated in four sessions to obtain either finger skin temperatures (FSTs) during cooling and rewarming of the hand or finger systolic blood pressures (FSBPs) after local cooling of the fingers to 15 and 10 °C. The measures were obtained with the room temperature at either 20 or 28 °C. Results: There were lower baseline finger skin temperatures, longer finger rewarming times, and lower finger systolic blood pressures with the room temperature at 20 than 28 °C. However, percentage reductions in FSBP at 15 and 10 °C relative to 30 °C (i.e. %FSBP) did not differ between the two room temperatures. Females had lower baseline FSTs, longer rewarming times, and lower FSBPs than males, but %FSBPs were similar in males and females. Conclusions: Finger rewarming times after cold provocation are heavily influenced by room temperature and gender. For evaluating peripheral circulatory function using finger rewarming times, the room temperature must be strictly controlled, and a different diagnostic criterion is required for females. The calculation of percentage changes in finger systolic blood pressure at 15 and 10 °C relative to 30 °C reduces effects of both room temperature and gender, and the test may be used in conditions where the ±1 °C tolerance on room temperature required by the current standard cannot be achieved. [ABSTRACT FROM AUTHOR]

Platelets contribute to thrombus formation in a variety of ways. Platelet adhesion, activation, and thrombus growth depend greatly on the type of hemodynamic environment surrounding an inciting event. Microfluidic systems may be used to explore these relationships. In this review, we describe some important considerations required in the design of a microfluidic system and identify some limitations that may require use of a macroscale system. [ABSTRACT FROM PUBLISHER]

Sleep disturbance may be the most often endorsed symptom of posttraumatic stress disorder (PTSD). Much of this research is based on subjective reports from trauma survivors; however, objective measures of sleep-related impairment have yielded findings inconsistent with self-report data. More studies investigating subjective and objective assessments concordantly are needed to understand sleep impairment in PTSD. The current study examined PTSD-related sleep disturbance in a female interpersonal violence cohort with full PTSD diagnoses ( N =51) assessing subjective (global and daily diary measures) and objective (actigraphy) sleep measures concurrently. PTSD severity was positively associated with global, subjective reports of sleep impairment and insomnia. Subjective measures of sleep (including global sleep impairment, insomnia, and daily sleep diary reports of total sleep time, sleep efficiency, and sleep onset latency) were moderately to strongly correlated. However, no significant correlations between subjective and objective reports of sleep impairment were found in this cohort. Analyses demonstrated an overall elevation in subjectively reported sleep impairment when compared to objective measurement assessed concurrently. Findings demonstrate a lack of agreement between subjective and objective measurements of sleep in a PTSD-positive female cohort, suggesting objective and subjective sleep impairments are distinct sleep parameters that do not necessarily directly co-vary. [ABSTRACT FROM AUTHOR]

Backrests influence the comfort of seated people. With 21 subjects sitting with three backrest heights (no backrest, short backrest, high backrest) discomfort caused by lateral, roll, and fully roll-compensated lateral oscillation was investigated at frequencies between 0.25 and 1.0 Hz. With lateral oscillation, the short backrest reduced discomfort at frequencies less than 0.63 Hz and the high backrest reduced discomfort at frequencies less than 1.0 Hz. With roll oscillation, the high backrest reduced discomfort at frequencies less than 0.63 Hz, but increased discomfort at 1.0 Hz. With fully roll-compensated lateral oscillation, the short backrest reduced discomfort at 0.4 Hz and the high backrest reduced discomfort at 0.5 and 0.63 Hz. As predicted by current standards, a backrest can increase discomfort caused by high frequencies of vibration. However, a backrest can reduce discomfort caused by low frequencies, with the benefit depending on the frequency and direction of oscillation and backrest height. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated whether the reductions in finger blood flow induced by 125-Hz vibration applied to different locations on the hand depend on thresholds for perceiving vibration at these locations. Methods: Subjects attended three sessions during which vibration was applied to the right index finger, the right thenar eminence, or the left thenar eminence. Absolute thresholds for perceiving vibration at these locations were determined. Finger blood flow in the middle finger of both hands was then measured at 30-s intervals during five successive 5-min periods: (i) pre-exposure, (ii) pre-exposure with 2-N force, (iii) 2-N force with vibration, (iv) post-exposure with 2-N force, (v) recovery. During period (iii), vibration was applied at 15 dB above the absolute threshold for perceiving vibration at the right thenar eminence. Results: Vibration at all three locations reduced finger blood flow on the exposed and unexposed hand, with greater reductions when vibrating the finger. Vibration-induced vasoconstriction was greatest for individuals with low thresholds and locations of excitation with low thresholds. Conclusions: Differences in vasoconstriction between subjects and between locations are consistent with the Pacinian channel mediating both absolute thresholds and vibration-induced vasoconstriction. [ABSTRACT FROM AUTHOR]

A series of metal and metal phosphide catalysts were investigated for the hydrodeoxygenation of guaiacol under ex situ catalytic fast pyrolysis conditions (350 °C, 0.5 MPa, 12 H:1 guaiacol, weight hourly space velocity 5 h). Ligand-capped Ni, Pt, Rh, NiP, and RhP nanoparticles (NPs) were prepared using solution-phase synthesis techniques and dispersed on a silica support. For the metal phosphide NP-catalysts, a synthetic route that relies on the decomposition of a single molecular precursor was employed. The reactivity of the NP-catalysts was compared to a series of reference materials including Ni/SiO and Pt/SiO prepared using incipient wetness (IW) impregnation and a commercial (com) Pt/SiO catalyst. The NP-Ni/SiO catalyst exhibited the largest reduction in the oxygen mol% of the organic phase and outperformed the IW-Ni/SiO material. Although it was less active for guaiacol conversion than NP-Ni/SiO, NP-RhP/SiO demonstrated the largest production of completely deoxygenated products and the highest selectivity to anisole, benzene, and cyclohexane, suggesting that it is a promising catalyst for deoxygenation of aryl-OH bonds. The com-Pt/SiO and IW-Pt/SiO catalyst exhibited the highest normalized rate of guaiacol conversion per m and per gram of active phase, respectively, but did not produce any completely deoxygenated products. [ABSTRACT FROM AUTHOR]

The detection of a vibration may be reduced by the presence of another vibration: a phenomenon known as ‘masking’. This study investigated how the detection of one frequency of vibration is influenced by vibration at another frequency. With nine subjects, thresholds for detecting fore-and-aft backrest vibration were determined (for 4, 8, 16, and 31.5-Hz sinusoidal vibration) in the presence of a masker vibration (4-Hz random vibration, 1/3-octave bandwidth at six intensities). The masker vibration increased thresholds for perceiving vibration at each frequency by an amount that reduced with increasing difference between the frequency of the sinusoidal vibration and the frequency of the masker vibration. The 4-Hz random vibration almost completely masked 4-Hz sinusoidal vibration, partially masked 8- and 16-Hz vibration, and only slightly masked 31.5-Hz vibration. The findings might be explained by the involvement of different sensory systems and different body locations in the detection of different frequencies of vibration. [ABSTRACT FROM AUTHOR]

There are two families of Donaldson invariants for the complex projective plane, corresponding to the SU(2)-gauge theory and the SO(3)-gauge theory with non-trivial Stiefel-Whitney class. In 1997 Moore and Witten conjectured that the regularized u-plane integral on ℂgives the generating functions for these invariants. In earlier work, the second two authors proved the conjecture for the SO(3)-gauge theory. Here we complete the proof of the conjecture by confirming the claim for the SU(2)-gauge theory. As a consequence, we find that the SU(2)-Donaldson invariants for ℂ are explicit linear combinations of the Hurwitz class numbers which arise in the theory of imaginary quadratic fields and orders. [ABSTRACT FROM AUTHOR]

The discomfort caused by lateral oscillation, roll oscillation, and fully roll-compensated lateral oscillation has been investigated at frequencies between 0.25 and 1.0 Hz when sitting on a rigid seat and when sitting on a compliant cushion, both without a backrest. Judgements of vibration discomfort and the transmission of lateral and roll oscillation through the seat cushion were obtained with 20 subjects. Relative to the rigid seat, the cushion increased lateral acceleration and roll oscillation at the lower frequencies and also increased discomfort during lateral oscillation (at frequencies less than 0.63 Hz), roll oscillation (at frequencies less than 0.4 Hz), and fully roll-compensated lateral oscillation (at frequencies between 0.315 and 0.5 Hz). The root-sums-of-squares of the frequency-weighted lateral and roll acceleration at the seat surface predicted the greater vibration discomfort when sitting on the cushion. The frequency-dependence of the predicted discomfort may be improved by adjusting the frequency weighting for roll acceleration at frequencies between 0.25 and 1.0 Hz. [ABSTRACT FROM AUTHOR]

The extent to which a seat can provide useful attenuation of vehicle vibration depends on three factors: the characteristics of the vehicle motion, the vibration transmissibility of the seat, and the sensitivity of the body to vibration. The ‘seat effective amplitude transmissibility’ (i.e., SEAT value) reflects how these three factors vary with the frequency and the direction of vibration so as to predict the vibration isolation efficiency of a seat. The SEAT value is mostly used to select seat cushions or seat suspensions based on the transmission of vertical vibration to the principal supporting surface of a seat. This study investigated the accuracy of SEAT values in predicting how seats with backrests influence the discomfort caused by multiple-input vibration. Twelve male subjects participated in a four-part experiment to determine equivalent comfort contours, the relative discomfort, the location of discomfort, and seat transmissibility with three foam seats and a rigid reference seat at 14 frequencies of vibration in the range 1–20 Hz at magnitudes of vibration from 0.2 to 1.6 ms −2 r.m.s. The ‘measured seat dynamic discomfort’ (MSDD) was calculated for each foam seat from the ratio of the vibration acceleration required to cause similar discomfort with the foam seat and with the rigid reference seat. Using the frequency weightings in current standards, the SEAT values of each seat were calculated from the ratio of overall ride values with the foam seat to the overall ride values with the rigid reference seat, and compared to the corresponding MSDD at each frequency. The SEAT values provided good predictions of how the foam seats increased vibration discomfort at frequencies around the 4-Hz resonance but reduced vibration discomfort at frequencies greater than about 6.3 Hz, with discrepancies explained by a known limitation of the frequency weightings. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated how the vasoconstriction induced by vibration depends on the frequency of vibration when the vibration magnitude is defined by individual thresholds for perceiving vibration [i.e. sensation levels (SL)]. Methods: Fourteen healthy subjects attended the laboratory on seven occasions: for six vibration frequencies (8, 16, 31.5, 63, 125, or 250 Hz) and a static control condition. Finger blood flow (FBF) was measured in the middle fingers of both hands at 30-second intervals during five successive periods: (i) no force or vibration, (ii) 2-N force, no vibration, (iii) 2-N force, vibration, (iv) 2-N force, no vibration, (v) no force or vibration. During period (iii), vibration was applied to the right thenar eminence via a 6-mm diameter probe during ten successive 3-min periods as the vibration magnitude increased in ten steps (−10 to +40 dB SL). Results: With vibration at 63, 125, and 250 Hz, there was vasoconstriction on both hands when the vibration magnitude reached 10 dB SL. With vibration at 8, 16, and 31.5 Hz, there was no significant vasoconstriction until the vibration reached 25 dB SL. At all frequencies, there was greater vasoconstriction with greater magnitudes of vibration. Conclusions: It is concluded that at the higher frequencies (63, 125, and 250 Hz), the Pacinian channel mediates vibrotactile sensations near threshold and vasoconstriction occurs when vibration is perceptible. At lower frequencies (8, 16, and 31.5 Hz), the Pacinian channel does not mediate sensations near threshold and vasoconstriction commences at greater magnitudes when the Pacinian channel is activated. [ABSTRACT FROM AUTHOR]

We investigate ξ (s) = 1 2 s (s − 1) π − s 2 Γ (s 2) ζ (s) , where ζ (s) is the Riemann zeta function. The Riemann hypothesis (RH) asserts that if ξ (s) = 0 , then Re (s) = 1 2. Pólya proved that RH is equivalent to the hyperbolicity of the Jensen polynomials J d , n (X) constructed from certain Taylor coefficients of ξ (s). For each d ≥ 1 , recent work proves that J d , n (X) is hyperbolic for sufficiently large n. In this paper, we make this result effective. Moreover, we show how the low-lying zeros of the derivatives ξ (n) (s) influence the hyperbolicity of J d , n (X). [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The affinity constants of a ligand for active and inactive states of a receptor ultimately determine its capacity to activate downstream signaling events. In this report, we describe a reverse-engineering strategy for estimating these microscopic constants. Methods: Our approach involves analyzing responses measured downstream in the signaling pathway of a G protein-coupled receptor under conditions of allosteric modulation and reduced receptor expression or partial receptor inactivation. The analysis also yields estimates of the isomerization constant of the unoccupied receptor, the sensitivity constant of the signaling pathway, and the more empirical parameters of the receptor population including the observed affinities and efficacies of allosteric and orthosteric ligands – including inverse agonists – and the efficacy of the unoccupied receptor (i.e., constitutive activity). Results and discussion: We validate our approach with an analytical proof and by analysis of simulated data. We also use our method to analyze data from the literature. We show that the values of the microscopic constants of orthosteric and allosteric ligands are constant regardless of the allosteric interaction and the nature of the receptor-signaling pathway as long as the same active state mediates the response. Our analysis is useful for quantifying probe-dependent allosteric interactions and the selectivity of agonists for different signaling pathways. Knowing the isomerization constant and sensitivity constant of a signaling pathway in a given cell line or tissue preparation enables future investigators to estimate the affinity constants of agonists for receptor states simply through analysis of their concentration–response curves. Our approach also provides a means of validating in silico estimates of ligand affinity for crystal structures of active and inactive states of the receptor. [Copyright &y& Elsevier]

Abstract: Previous research has suggested that faces and words are processed and remembered differently as reflected by different ERP patterns for the two types of stimuli. Specifically, face stimuli produced greater late positive deflections for old items in anterior compared to posterior regions, while word stimuli produced greater late positive deflections in posterior compared to anterior regions. Given that words have existing representations in subjects׳ long-term memories (LTM) and that face stimuli used in prior experiments were of unknown individuals, we conducted an ERP study that crossed face and letter stimuli with the presence or absence of a prior (stable or existing) memory representation. During encoding, subjects judged whether stimuli were known (famous face or real word) or not known (unknown person or pseudo-word). A surprise recognition memory test required subjects to distinguish between stimuli that appeared during the encoding phase and stimuli that did not. ERP results were consistent with previous research when comparing unknown faces and words; however, the late ERP pattern for famous faces was more similar to that for words than for unknown faces. This suggests that the critical ERP difference is mediated by whether there is a prior representation in LTM, and not whether the stimulus involves letters or faces. [Copyright &y& Elsevier]

While body image concerns and interpersonal violence exposure are significant issues for women, their interrelationship has rarely been explored. We examined the associations between severity of acute injuries, symptoms of posttraumatic stress disorder (PTSD), depression, and body image distress within a sample of predominantly African American victims of interpersonal violence (N = 73). Severity of body image distress was significantly associated with each outcome. Moreover, body image distress was a significant, unique predictor of depression but not PTSD severity. We recommend continued exploration of body image concerns to further integrated research on violence against women. [ABSTRACT FROM AUTHOR]

Abstract: While walking on an instrumented treadmill, 20 subjects were perturbed by lateral sinusoidal oscillations representative of those encountered in transport: frequencies in the range 0.5–2 Hz and accelerations in the range 0.1–2.0 ms−2 r.m.s., corresponding to velocities in the range 0.032–0.16 ms−1 r.m.s. Postural stability was assessed from the self-reported probability of losing balance (i.e., perceived risk of falling) and the movements of the centre of pressure beneath the feet. With the same acceleration at all frequencies, the velocities and displacements of the oscillatory perturbations were greater with the lower frequency oscillations, and these caused greater postural instability. With the same velocity at all frequencies, postural instability was almost independent of the frequency of oscillation. Movements of the centre of pressure show that subjects attempted to compensate for the perturbations by increasing their step width and increasing their step rate. [Copyright &y& Elsevier]