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We construct the first infinite families of locally 2-arc transitive graphs with the property that the automorphism group has two orbits on vertices and is quasiprimitive on exactly one orbit, of twisted wreath type. This work contributes to Giudici, Li and Praeger’s program for the classification of locally 2-arc transitive graphs by showing that the star normal quotient twisted wreath category also contains infinitely many graphs.

Using the historical experience from past monetary tightening cycles and the market-expected path of the federal funds rate for the current tightening cycle, we project that the flows from bank deposits to money market funds (MMFs) would be relatively small, at about $600 billion through the end of 2024, or about 3 percent of current bank deposits. Of these potential inflows to MMFs, about $100 billion are projected to flow into the overnight reverse repo (ON RRP) facility, or about 7 percent of MMFs’ recent take-up. Other factors such as the private demand for repo funding and the net supply of Treasury bills are expected to have more substantial effects on MMFs’ take-up at the ON RRP facility than the inflows from bank deposits.

An LR-structure is a tetravalent vertex-transitive graph together with a special type of a decomposition of its edge-set into cycles. LR-structures were introduced in a paper by P. Poto\v{c}nik and S. Wilson, titled `Linking rings structures and tetravalent semisymmetric graphs', in Ars Math. Contemp. 7 (2014), as a tool to study tetravalent semisymmetric graphs of girth 4. In this paper, we use the methods of group amalgams to resolve some problems left open in the above-mentioned paper.

In 1564, Pierfrancesco ‘Vicino’ Orsini wrote to the humanist Annibale Caro to request advice about the frescoes of a loggia of his palazzo in the town of Bomarzo.1 Orsini had already chosen the sub...

A Cayley graph for a group G is CCA if every automorphism of the graph that preserves the edge-orbits under the regular representation of G is an element of the normaliser of G. A group G is then said to be CCA if every connected Cayley graph on G is CCA. We show that a finite simple group is CCA if and only if it has no element of order 4. We also show that “many” 2-groups are non-CCA.

Fumonisins are a group of mycotoxins that routinely contaminate maize. Their presence is monitored at multiple stages from harvest to final product. Immunoassays are routinely used to screen commodities in the field while laboratory-based methods, such as mass spectrometry (MS), are used for confirmation. The use of a portable mass spectrometer unlocks the potential to conduct confirmatory analyses outside of traditional laboratories. Herein, a portable mass spectrometer was used to measure fumonisins in maize. Samples were extracted with aqueous methanol, cleaned up on an immunoaffinity column, and tested with the portable MS. The limits of detection were 0.15, 0.19, and 0.28 mg/kg maize for fumonisins B1 (FB1), FB2/FB3, and total fumonisins, respectively. The corresponding limits of quantitation in maize were 0.33, 0.59, and 0.74 mg/kg. Recoveries ranged from 93.6% to 108.6%. However, RSDs ranged from 12.0 to 29.8%. The method was applied to the detection of fumonisins in 64 samples of maize collected as part of the Illinois Department of Agriculture’s monitoring program. Good correlations were observed between the portable MS and a laboratory-based LC-MS method (r2 from 0.9132 to 0.9481). Results suggest the portable MS can be applied to the measurement of fumonisins in maize at levels relevant to international regulations.

This article examines Heinrich Wolfflin’s discussion of sixteenth-century Italian landscape design in Renaissance and Baroque (1888). It argues that Wolfflin’s interpretation influenced twentieth-c...

Let $p$ be an odd prime. We construct a $p$-group $P$ of nilpotency class two, rank seven and exponent $p$, such that $\text{Aut}(P)$ induces $N_{\text{GL}(7,p)}(G_{2}(p))=Z(\text{GL}(7,p))G_{2}(p)$ on the Frattini quotient $P/\unicode[STIX]{x1D6F7}(P)$. The constructed group $P$ is the smallest $p$-group with these properties, having order $p^{14}$, and when $p=3$ our construction gives two nonisomorphic $p$-groups. To show that $P$ satisfies the specified properties, we study the action of $G_{2}(q)$ on the octonion algebra over $\mathbb{F}_{q}$, for each power $q$ of $p$, and explore the reducibility of the exterior square of each irreducible seven-dimensional $\mathbb{F}_{q}[G_{2}(q)]$-module.

Dolfi, Guralnick, Praeger and Spiga asked whether there exist infinitely many primitive groups of twisted wreath type with non-trivial coprime subdegrees. Here, we settle this question in the affirmative. We construct infinite families of primitive twisted wreath permutation groups with non-trivial coprime subdegrees. In particular, we define a primitive twisted wreath groupG(m,q) constructed from the non-abelian simple group PSL(2,q) and a primitive permutation group of diagonal type with socle PSL(2,q)m, and determine many subdegrees for this group. A consequence is that we determine all values ofmandqfor whichG(m,q) has non-trivial coprime subdegrees. In the case wherem= 2 and$q\notin \{7,11,29\}$, we obtain a full classification of all pairs of non-trivial coprime subdegrees.

We characterise the primitive 2-closed groups $G$ of rank at most four that are not the automorphism group of a graph or digraph and show that if the degree is at least 2402 then there are just two infinite families or $G\leqslant \mathrm{A}\Gamma\mathrm{L}_1(p^d)$, the 1-dimensional affine semilinear group. These are the first known examples of non-regular 2-closed groups that are not the automorphism group of a graph or digraph.

Secondary aorto-enteric fistulas (AEFs) are an uncommon but serious complication of abdominal aortic aneurysm (AAA) repair. Case review of two cases of secondary AEF are as follows: the first case involved a 75-year- old male who presented with AEF 1 year post-emergency open AAA repair, successfully managed with endovascular aortic aneurysm repair (EVAR) without complication. The second case involved a 75-year-old male patient 14 months post open AAA repair for an inflammatory aneurysm who presented with an iliac-enteric fistula. The previous repair was relined with a bifurcated EVAR with subsequent laparotomy and resection of the affected portion of the small bowel. Both patients on lifelong antibiotics without further episodes of sepsis, recurrence of AEF or mortality at 12 months follow up. EVAR can be successful in the management of secondary AEF. Careful patient selection, accurate image interpretation, and expedient management are key factors to successful short- and long-term outcomes.

A transitive permutation group is semiprimitive if each of its normal subgroups is transitive or semiregular. Interest in this class of groups is motivated by two sources: problems arising in universal algebra related to collapsing monoids and the graph-restrictive problem for permutation groups. Here we develop a theory of semiprimitive groups which encompasses their structure, their quotient actions and a method by which all finite semiprimitive groups are constructed. We also extend some results from the theory of primitive groups to semiprimitive groups, and conclude with open problems of a similar nature., Comment: 34 pages

The aim of this study was to establish the capability of X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) methods to determine different spodumene forms (α-, β- and γ-spodumene) occurring during heat treatment of lithium spodumene. It is essential to correctly identify and quantify the presence of different forms of spodumene after heat treatment to ensure optimum lithium extraction. A sample from the Haapaluoma lithium-pegmatite (western Finland) was used for this study. An experimental programme was initiated to model the progression of the mineral transformation at different stages through heat treatment. The specimen was broken down and split into five portions. One of the splits was analysed unheated with XRD, FTIR, XRF and ICP; the other four splits were analysed with XRD and FTIR after heat treatment at different temperatures from 850 to 1100 °C. In this study, we show that both laboratory-based XRD and portable FTIR methods are effective in identifying and quantifying α-, β- and γ-spodumene as well as impurities. The accuracy of the quantification of the minerals with XRD was established by using a mass balance calculation and was compared with the actual chemistry of the sample measured with ICP analysis. Fully quantitative XRD analysis of heat-treated spodumene is considered a challenge due to peak overlaps between the β-, and γ-spodumene forms, particularly when gangue minerals and amorphous content are present. The novelty of this study consists of the use of the XRD technique complemented by the Rietveld method to fully quantify the different forms of spodumene from one another: α-, β- and γ-spodumene, along with the gangue minerals and the amorphous content. It is also shown that reproducible systematic changes occur in the FTIR spectra that track the spodumene transformation during heat treatment. With more samples and cross-validation between the XRD results, the FTIR methodology could be developed further to provide semi-quantitative information on the different spodumene forms in the future. This would permit the use of a fast, cost-effective and portable technique for quality control of the spodumene forms, which would open opportunities across the Li value chain.

The First Amendment to the Constitution guarantees “freedom . . . of the press,” making an explicit textual recognition of what the founding generation, informed by their immediate historical experience, frequently hailed as the most important political liberty—the “bulwark” upon which all other freedoms relied. From this fertile intellectual and legal soil, cultivated by generous subsidies, a thriving and vibrant institutional press emerged as an undeniable asset to American civil society. Today, that press is dying. Industry revenues have declined by more than 70% in the last two decades, leaving tens of thousands of journalists without jobs and millions of Americans without meaningful access to quality journalism. The reason for this media apocalypse is simple: America has assigned to the free market the task of producing an adequate supply of a public good, with most of its value lying in externalities, that cannot be made profitable to the same extent that it is desirable. As a result, American journalism is in a market-induced death spiral. This Article argues that, given the Framers’ correct understanding that a sustainable, powerful institutional press is a precondition to representative government, the market-driven collapse of the press is a constitutional crisis.

The mathematics of shuffling a deck of $2n$ cards with two "perfect shuffles" was brought into clarity by Diaconis, Graham and Kantor. Here we consider a generalisation of this problem, with a so-called "many handed dealer" shuffling $kn$ cards by cutting into $k$ piles with $n$ cards in each pile and using $k!$ shuffles. A conjecture of Medvedoff and Morrison suggests that all possible permutations of the deck of cards are achieved, so long as $k\neq 4$ and $n$ is not a power of $k$. We confirm this conjecture for three doubly infinite families of integers: all $(k,n)$ with $k>n$; all $(k, n)\in \{ (\ell^e, \ell^f )\mid \ell \geqslant 2, \ell^e>4, f \ \mbox{not a multiple of}\ e\}$; and all $(k,n)$ with $k=2^e\geqslant 4$ and $n$ not a power of $2$. We open up a more general study of shuffle groups, which admit an arbitrary subgroup of shuffles.

The distinguishing number of $G \leqslant \sym(\Omega)$ is the smallest size of a partition of $\Omega$ such that only the identity of $G$ fixes all the parts of the partition. Extending earlier results of Cameron, Neumann, Saxl and Seress on the distinguishing number of finite primitive groups, we show that all imprimitive quasiprimitive groups have distinguishing number two, and all non-quasiprimitive semiprimitive groups have distinguishing number two, except for $\mathrm{GL}(2, 3)$ acting on the eight non-zero vectors of $\mathbb F_2^3$, which has distinguishing number three., Comment: 10 pages

One of the earliest literary representations of ruins in a landscape setting appears in Francesco Colonna’s antiquarian romance, Hypnerotomachia Poliphili (1499) (figure 1). Encountering huge ruine...

Early modern art features a remarkable fascination with ornament, both as decorative device and compositional strategy, across artistic media and genres. Interestingly, the inventive, elegant manifestations of ornament in the art of the period often include layers of disquieting paradoxes, creating tensions - monstrosities even - that manifest themselves in a variety of ways. In some cases, dichotomies (between order and chaos, artificiality and nature, rational logic and imaginative creativity, etc.) may emerge. Elsewhere, a sense of agitation undermines structures of statuesque control or erupts into wild, unruly displays of constant genesis. The monstrosity of ornament is brought into play through strategies of hybridity and metamorphosis, or by the handling of scale, proportion, and space in ambiguous and discomforting ways that break with the laws of physical reality. An interest in strange exaggeration and curious artifice allows for such colossal ornamental attitude to thrive within early modern art.

Addictive products—tobacco, alcohol, gambling, and the like—have been considered legitimate regulatory targets for millennia, a tradition into which both Founding-era and modern America comfortably fits. Expressive products—newspapers, books, movies, and video games—on the other hand, have been considered essentially immune from content-based regulation, thanks to the First Amendment. But what if the content of an expressive product makes it addictive? Which tradition must give in: the ancient ability of legislatures to protect society at large from the wide-ranging impacts of addiction, or the legal shield that has generated a thriving culture of artistic independence? This Article is the first to explore the question of how the First Amendment should treat intentionally addictive speech. Social scientists indicate that certain behavioral addictions premised on compulsive use of expressive products—in particular, video games and pornography—are real dysfunctions of the brain, explainable in part by the intentional choices of developers and producers to create addictive products. And regulators are beginning to unsteadily lurch into action, without any evidence that they are taking the First Amendment into account. This Article proposes that, under current doctrine, any such regulation would need to satisfy strict scrutiny. It then argues for a departure and a recognition that intentionally addictive expression does not merit First Amendment coverage.

Introduction Transarterial embolization (TAE) and transarterial chemoembolization (TACE) are established treatments for symptom control in patients with advanced neuroendocrine tumors (NETs) with significant hepatic tumor burden. Aim To assess efficacy, toxicity and survival parameters in NET patients undergoing TAE and TACE. Materials and Methods A retrospective analysis was carried out of 50 patients with NETs, who underwent a total of 67 embolization procedures in a period of 9 years. All patients had symptomatic and/or radiological progression, despite previous treatments. Results Symptomatic improvement was observed in 75% of patients who underwent TAE and 57% of patients who had TACE (P = 0.36). Radiological response was observed following 73% of embolization treatments delivered and specifically in 82% of all TAE and 62% of all TACE procedures (P = 0.46). Plasma Chromogranin A (CgA) levels were reduced in 65% of the patients following embolization. Patients with increasing serum CgA levels after treatment had reduced median overall survival (OS) and progression-free survival (PFS) (P = 0.0001). Patients on somatostatin analogs (SSAs) at the time of treatment had improved OS (P = 0.013), but not PFS (P = 0.216). Overall, the differences in OS (P = 0.21) and PFS (P = 0.19) between one mode of treatment over the other were not found to be statistically significant. One- and 5-year OS were 65% and 41% for TACE and 90% and 57% for TAE, respectively. The commonest complication was postembolization syndrome and mortality was 4%. Overall, the complication (P = 0.18) and mortality rates (P = 0.22) were not significantly different between TAE and TACE. Conclusions TAE/TACE are beneficial treatments for control of symptoms as well as tumor growth, with acceptable morbidity and mortality rates. No significant efficacy and survival differences were shown between TAE and TACE. Posttreatment CgA levels and the concurrent use of SSAs were independently associated with survival.