Publications by authors named "MAHON M"

The group 1 alumanyls, [{SiN}AlM] (M = K, Rb, Cs; SiN = {CHSiMeNDipp}), display a variable kinetic facility (K < Rb < Cs) toward oxidative addition of the acidic C-H bond of terminal alkynes to provide the corresponding alkali metal hydrido(alkynyl)aluminate derivatives. Theoretical analysis of the formation of these compounds through density functional theory (DFT) calculations implies that the experimentally observed changes in reaction rate are a consequence of the variable stability of the [{SiN}AlM] dimers, the integrity of which reflects the ability of M to maintain the polyhapto group 1-arene interactions necessary for dimer propagation. These observations highlight that such "on-dimer" reactivity takes place sequentially and also that the ability of each constituent Al(I) center to effect the activation of the organic substrate is kinetically differentiated.

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Spatial hearing relies on the encoding of perceptual sound location cues in space. It is critical for communicating in background noise, and understanding where sounds are coming from (sound localization). Although there are some monoaural spatial hearing cues (i.

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Article Synopsis
  • Neoadjuvant radiotherapy is crucial for treating locally advanced rectal cancer, and this study compares the quality-of-life outcomes between two techniques: three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT).
  • A phase II randomized trial involved 94 patients who received chemoradiotherapy and were assigned to either 3DCRT or IMRT; their quality of life was assessed using specific questionnaires throughout the treatment and at a six-month follow-up.
  • Although the trial ended early due to the futility of its primary endpoint, the results indicated that while emotional functioning improved, other aspects of quality of life declined; notably, IMRT showed better physical and role functioning during the final week
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Reactions of a m-terphenylhydridostannylene with β-diketiminato magnesium and calcium hydrides provide bis-μ-hydrido species, the heterobimetallic constitutions of which are maintained after the addition of THF donor solvent. In both cases, reactions with hex-1-ene result in the formation of tetravalent organostannyl alkaline earth derivatives. Whereas the magnesium reagent undergoes facile twofold addition, the calcium-centered process is arrested after a single alkene reduction event.

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The dimeric calcium and magnesium hydrides, [(BDI)AeH] [BDI=HC{(Me)CNDipp}, Dipp=2,6-i-PrCH; Ae=Mg or Ca] do not react with PhGeH in non-coordinating solvent. Addition of THF, however, induces deprotonation and access to monomeric Ae-germanide complexes, [(BDI)Ae{GePh}(THF)], both of which have been structurally characterized. Although this process is facile when Ae=Ca, the analogous magnesium-based reaction requires heating to temperatures >100 °C, under which conditions germanide formation is complicated by THF ring opening and the generation of an alkaline earth germyl-C-terminated n-butoxide, [(BDI)Mg{μ-O(CH)GePh}].

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The reaction of [Ir(IPr)H][BAr] (; IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene; BAr = B{CH(3,5-CF)}) with ZnMe proceeds with CH elimination to give [Ir(IPr)(IPr')(ZnMe)H][BAr] (, where (IPr') is a cyclometalated IPr ligand). reacts with H to form tetrahydride [Ir(IPr)(ZnMe)H][BAr], , that loses H under forcing conditions to form [Ir(IPr)(ZnMe)H][BAr], . Crystallization of also results in the formation of its noncyclometalated isomer, [Ir(IPr)(ZnMe)][BAr], , in the solid state.

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Introduction: Despite proven effectiveness in refractory schizophrenia, clozapine remains underutilised, and it is important to understand potential reasons for this. This study's aim was to examine in a National sample of Consultant Psychiatrists their knowledge of, attitudes and perceived barriers to clozapine use.

Methods: A novel questionnaire was designed and distributed by email to 275 Consultant Psychiatrists in Republic of Ireland.

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The behavior of the potassium alumanyl, [{SiN}AlK] ({SiN} = {CHSiMeN(Dipp)}; Dipp = 2,6--PrCH), toward organic nitriles has been investigated. In common with earlier studies of the reactivity of charge neutral Al(I) species with multiply bonded small molecules, it is suggested that the initial step in all the reactions involves [2 + 1] cycloaddition and the generation of an [η-C=N-Al] alumina azacyclopropane unit. In the cases of - and -tolyl-substituted aryl nitriles, this species is too kinetically labile to allow its isolation and undergoes C-C coupling via immediate Al-C/C≡N insertion to yield the alumina diazabutadiene derivatives.

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Range maps are used to estimate the geographic extent of taxa, providing valuable information for biodiversity and conservation research and management. Freshwater macroinvertebrates are not well-represented in the range map literature relative to freshwater vertebrates. To address this knowledge gap, we provide range maps for 1158 freshwater macroinvertebrate genera based on two decades of publicly available occurrence data from the USEPA National Aquatic Resource Surveys, which included 11,628 sites and 6,906,990 organisms across the contiguous USA.

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[{SiN}BeClM] ({SiN} = {CHSiMeN(Dipp)}; M = Li, Na, K, Rb) are converted to ionic species by treatment with a crown ether. Whereas the lithium derivative reacts with Na or K to provide [{SiN}BeCl][M(12-cr-4)] (M = Na, K), the resultant sodium species is resistant to reduction by potassium. These observations are rationalised by a hybrid experimental/theoretical analysis.

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Cycle threshold (CT) refers to the number of cycles in a reverse transcriptase polymerase chain reaction (RT-PCR) assay needed to amplify viral RNA and can be used to indicate viral load. CT is inversely related to viral load, where lower CT values indicate higher viral levels. Data suggest lower CT scores are associated with worse outcomes in COVID; however, quantitative CT scores are not typically reported to patients.

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Article Synopsis
  • The compound [(BDI)CaH], which contains a calcium hydride and a special ligand (BDI), reacts with zinc methyl (ZnMe).
  • This reaction produces a bimetallic complex named [(BDI)Ca(μ-CH)Zn(μ-H)], which has both calcium and zinc in its structure.
  • The complex then undergoes an intramolecular reaction to create [(BDI)CaMe], highlighting its unique presence within the series of related calcium compounds.
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We asked whether grammatical number marking has specific influence on the formation of early number concepts. In particular, does comprehension of dual case marking support young children's understanding of cardinality? We assessed number knowledge in 77 3-year-old Arabic-English bilingual children using the Give-a-Number task in both languages. Given recent concerns around the administration and scoring of the Give-a-Number task, we used two complementary approaches: one based on conceptual levels and the other based on overall test scores.

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Small-cell lung cancer (SCLC) is the most fatal form of lung cancer. Intratumoral heterogeneity, marked by neuroendocrine (NE) and non-neuroendocrine (non-NE) cell states, defines SCLC, but the cell-extrinsic drivers of SCLC plasticity are poorly understood. To map the landscape of SCLC tumor microenvironment (TME), we apply spatially resolved transcriptomics and quantitative mass spectrometry-based proteomics to metastatic SCLC tumors obtained via rapid autopsy.

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Prostate cancer lung metastasis represents a clinical conundrum due to its implications for advanced disease progression and the complexities it introduces in treatment planning. As the disease progresses to distant sites such as the lung, the clinical management becomes increasingly intricate, requiring tailored therapeutic strategies to address the unique characteristics of metastatic lesions. This review seeks to synthesize the current state of knowledge surrounding prostate cancer metastasis to the lung, shedding light on the diverse array of clinical presentations encountered, ranging from subtle radiological findings to overt symptomatic manifestations.

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Reactions of β-diketiminato alkaline earth alkyldiboranate derivatives [(BDI)Ae{pinBB(R)pin}] (BDI = HC{(Me)CNDipp}; Dipp = 2,6-i-PrCH; Ae = Mg, R = -Bu or Ae = Ca, R = -hexyl) with -BuNC provide access to the respective group 2 derivatives of unprecedented diborata-allyl, {(pinB)CNBpin(-Bu)}, anions. Although the necessary mode of B-C bond cleavage implicated in these transformations could not be elucidated, further studies of the reactivity of magnesium triboranates toward isonitriles delivered a more general and rational synthetic access to analogous anionic moieties. Extending this latter reactivity to a less symmetric triboranate variant also provided an isomeric Mg-C-bonded dibora-alkyl species and sufficient experimental insight to prompt theoretical evaluation of this reactivity.

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Anthropogenic change is contributing to the rise in emerging infectious diseases, which are significantly correlated with socioeconomic, environmental and ecological factors. Studies have shown that infectious disease risk is modified by changes to biodiversity, climate change, chemical pollution, landscape transformations and species introductions. However, it remains unclear which global change drivers most increase disease and under what contexts.

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The bimetallic species, [{SiN}MgNa] [{SiN} = {CHSiMeN(Dipp)}; (Dipp = 2,6--PrCH)], is shown to be a potent reducing agent, able to effect one- or two-electron reduction of either dioxygen, TEMPO, anthracene, benzophenone, or diphenylacetylene. In most cases, the bimetallic reaction products imply that the dissimilar alkaline metal centers react with a level of cooperativity. EPR analysis of the benzophenone-derived reaction and the concurrent isolation of [{SiN}Mg(OCPh)], however, illustrate that treatment with such reducible, but -basic, species can also result in reactivity in which the metals provide independent reaction products.

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  • The study explores the reactions of iron(II) bisphosphine complexes with PH using NaBAr, which includes variations in the bisphosphine ligands.
  • Six different cationic terminal-bound PH complexes were isolated and characterized using NMR spectroscopy, single crystal X-ray diffraction, and mass spectrometry, with some complexes showing unusual bis- and tris-PH formations.
  • An iron(0) source was utilized to create a unique terminally bound iron-PH complex, showcasing the versatility and potential of these iron-phosphorus systems.
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Article Synopsis
  • - The study investigates the synthesis of β-diketiminato complexes of calcium and magnesium that react with carborane (-CBH) to form new complexes, specifically [(BDI)Mg(-CBH)] and [(BDI)Ca(-CBH)].
  • - The magnesium complex is a monomer with a distorted planar structure, while the calcium complex exhibits a puckered geometry due to intermolecular interactions, which can be altered when THF is added, leading to a 4-coordinate monomer.
  • - The magnesium complex [(BDI)Mg(-CBH)] reacts with various copper group metals to create rare examples of coinage metal complexes, demonstrating that these alkaline earth compounds can effectively facilitate transmetalation of the car
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Unsedated transnasal endoscopy (TNE) is an alternative method of examining the esophageal mucosa in pediatric patients with eosinophilic esophagitis (EoE), reducing cost, time, and risk associated with frequent surveillance esophagogastroduodenoscopies (EGD). Adequacy of transnasal esophageal biopsies for the evaluation of eosinophilic esophagitis histologic scoring system (EoEHSS) has not yet been evaluated. We compared procedure times, endoscopic findings, and EoEHSS scoring for EoE patients undergoing TNE versus standard EGD.

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Liquid assisted ball milling of [NHC]HBr (NHC = N-heterocyclic carbene) salts with copper(I) chloride, and a range of alkali metal complexes was shown to efficiently produce (NHC)CuX (NHC = normal or RE-NHC, X = halide, alkoxide, amide, alkyl, aryl; RE-NHC = ring-expanded NHC).

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Room temperature reaction of elemental cesium with the dimeric lithium chloroberyllate [{SiN}BeClLi] [{SiN} = {CHSiMeN(Dipp)}, where Dipp = 2,6-di-isopropylphenyl, in CD results in activation of the arene solvent. Although, in contrast to earlier observations of lithium and sodium metal reduction, the generation of a mooted cesium phenylberyllate could not be confirmed, this process corroborates a previous hypothesis that such beryllium-centered solvent activation also necessitates the formation of hydridoberyllium species. These observations are further borne out by the study of an analogous reaction performed in toluene, in which case the proposed generation of formally low oxidation state beryllium radical anion intermediates induces activation of a toluene C-H bond and the isolation of the polymeric cesium benzylberyllate, [Cs({SiN}BeCHCH)].

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Deprotonation of triphenyl germane with NHC-supported copper alkoxides afforded four novel (NHC)CuGePh complexes. Of these, (IPr)CuGePh (IPr = :C{N(2,6-iPrCH)CH}) was selected for further investigation. Analysis by EDA-NOCV indicates it to be a germyl nucleophile and its σ-bond metathesis reaction with a range of p-block halides confirmed it to be a convenient source of [PhGe].

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