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The question of whether weakly Sylow-permutable subgroups of locally finite groups are serial is studied. An affirmative answer is obtained for many types of group, particularly groups satisfying finiteness conditions or with some degree of commutativity.

Background Uphill quenching (UHQ) of heat treatable aluminium alloy components is a long established but rarely practiced or investigated method of reducing residual stresses. The efficacy of the technique has not been quantified on thin walled structures before and this investigation will address that deficiency. Objective To quantify the impact of uphill quenching on thin walled structure with regards to residual stress and warpage, and compare and contrast to both quenching into cold water and a 30% polyalkylene glycol (PAG) solution. Methods Rectilinear hollow boxes were made from the very high strength aerospace aluminium alloy 7449. These were heat treated and aged using a variety of processing methods including uphill quenching from -196 °C to 100 °C using steam. Residual stresses have been characterised using neutron and x-ray diffraction. Results Compared to conventional quenching into cold water, both PAG and UHQ are shown to significantly lower the residual stresses. However, while PAG quenching results in a large uniform reduction in both residual stress and warpage, UHQ is much more localised and limited to regions adjacent to direct steam impingement. These regions are also warped. The depth of penetration of the stress relief during UHQ is shown to be 5 mm. Conclusions While uphill quenching is shown to be capable of locally stress relieving an aluminium alloy, it is far less effective compared to PAG quenching.

A comprehensive account is given of the theory of metanilpotent groups with the minimal condition on normal subgroups. After reviewing classical material, many new results are established relating to the Fitting subgroup, the Hirsch–Plotkin radical, the Frattini subgroup, splitting and conjugacy, the Schur multiplier, Sylow structure and the maximal subgroups. Module theoretic and homological methods are used throughout.

In this work we study groups for which there is a countable set of proper subgroups with the property that every proper subgroup is contained in some member of the set. (C) 2018 Elsevier Inc. All rights reserved.

A PST-group is a group in which Sylow permutability is a transitive relation. A classification is given of the soluble minimax groups whose finite quotients are PST-groups.

We report on a Hubble Space Telescope search for rest-frame ultraviolet emission from the host galaxies of five far-infrared-luminous $z\simeq{}6$ quasars and the $z=5.85$ hot-dust free quasar SDSS J0005-0006. We perform 2D surface brightness modeling for each quasar using a Markov-Chain Monte-Carlo estimator, to simultaneously fit and subtract the quasar point source in order to constrain the underlying host galaxy emission. We measure upper limits for the quasar host galaxies of $m_J>22.7$ mag and $m_H>22.4$ mag, corresponding to stellar masses of $M_\ast, 22 pages, 13 figures. Accepted for publication in ApJ

Type 1 diabetes mellitus (T1D) is an autoimmune disorder where T lymphocytes damage the islet beta cells but B lymphocytes also play an important role. Although changes in peripheral B cell phenotype have been observed, little is known about the B cells that secrete the autoantibodies. We developed a sensitive B cell enzyme-linked immunospot assay (ELISpot assay) to detect individual B cell antibody responses to glutamic acid decarboxylase (GAD) and islet antigen-2 (IA-2). We found that even healthy donors have B cells that secrete antibodies in response to GAD and IA-2 in the ELISpot. There was increased B cell reactivity to autoantigens in the peripheral blood of individuals with newly-diagnosed, but not long-standing, type 1 diabetes. However, no correlation with serum autoantibody levels was found, indicating that additional factors such as antigen affinity or exposure to antigens in vivo are required for antibody secretion, and that even healthy donors have potentially autoreactive B cells.

The centers and cyclic radicals of generalized Baumslag–Solitar groups (GBS-groups) are studied. Criteria for their non-triviality are found and an algorithm to compute the center and cyclic radical is given. In addition, for each unimodular GBS-group, a GBS-cover, i.e., a GBS-group in whose underlying graph the weights around each vertex are constant in absolute value, is constructed. These groups are then characterized by a minimality property.

A PST-group is a group in which Sylow permutability is a transitive relation in the group. A classification is given of finitely generated hyperabelian groups all of whose finite quotients are PST-groups.

Aims/hypothesis Islet-specific autoantibodies can predict the development of type 1 diabetes. However, it remains unclear if B cells, per se, contribute to the causal pancreatic immunopathology. We aimed to identify phenotypic signatures of disease progression among naive and memory B cell subsets in the peripheral blood of individuals with type 1 diabetes. Methods A total of 69 participants were recruited across two separate cohorts, one for discovery purposes and the other for validation purposes. Each cohort comprised two groups of individuals with type 1 diabetes (one with newly diagnosed type 1 diabetes and the other with long-standing type 1 diabetes) and one group of age- and sex-matched healthy donors. The phenotypic characteristics of circulating naive and memory B cells were investigated using polychromatic flow cytometry, and serum concentrations of various chemokines and cytokines were measured using immunoassays. Results A disease-linked phenotype was detected in individuals with long-standing type 1 diabetes, characterised by reduced C-X-C motif chemokine receptor 3 (CXCR3) expression on switched (CD27+IgD−) and unswitched (CD27intermediateIgD+) memory B cells. These changes were associated with raised serum concentrations of B cell activating factor and of the CXCR3 ligands, chemokine (C-X-C motif) ligand (CXCL)10 and CXCL11. A concomitant reduction in CXCR3 expression was also identified on T cells. Conclusions/interpretation Our data reveal a statistically robust set of abnormalities that indicate an association between type 1 diabetes and long-term dysregulation of a chemokine ligand/receptor system that controls B cell migration. Electronic supplementary material The online version of this article (10.1007/s00125-018-4651-x) contains peer-reviewed but unedited supplementary material, which is available to authorised users.

The object of this work is to find classes of groups which possess only countably many maximal subgroups. Modules with countably many maximal submodules and group rings having countably many maximal right ideals are also investigated. Examples of soluble groups with uncountably many maximal subgroups are described.

Cohomological vanishing theorems in dimensions 1 and 2 are established for finite soluble groups. Applications are given to splitting and conjugacy theorems, and also to the structure of automorphism groups of finite soluble groups with nilpotent length at most 3.

We consider systems of companies which have financial interests in each other and develop principles by which the real interest of one company in another can be determined. The paper develops an algorithm to calculate true interests from a weighted digraph that encodes the direct and indirect mutual holdings of the companies.

For a large class of groups necessary and sufficient conditions are given for their group algebras to have the bounded splitting property.

It is shown that the generalized Baumslag-Solitar graphs which have soluble fundamental groups can be constructed from four simple types of graph by a process of decoration. The method of proof is elementary and employs the operations of pinching and contracting edges of graphs.

Groups which have at most n isomorphism classes of derived subgroups ( D n -groups) are studied. A complete classification of locally finite D 3 -groups into nine types is obtained.

The structure of groups which have at most two isomorphism classes of derived subgroups ($\mathfrak{D}$2-groups) is investigated. A complete description of $\mathfrak{D}$2-groups is obtained in the case where the derived subgroup is finite: the solution leads an interesting number theoretic problem. In addition, detailed information is obtained about soluble $\mathfrak{D}$2-groups, especially those with finite rank, where algebraic number fields play an important role. Also, detailed structural information about insoluble $\mathfrak{D}$2-groups is found, and the locally free $\mathfrak{D}$2-groups are characterized.

OBJECTIVE: To assess if exposure to repeat dose(s) of antenatal corticosteroids has beneficial effects on neurodevelopment and general health in mid-childhood, at 6 to 8 years’ corrected age. METHODS: Women at risk for very preterm birth, who had received a course of corticosteroids ≥7 days previously, were randomized to intramuscular betamethasone (11.4 mg Celestone Chronodose) or saline placebo, repeated weekly if risk of very preterm birth remained. Mid-childhood assessments included neurocognitive function, behavior, growth, lung function, blood pressure, health-related quality of life, and health service utilization. The primary outcome was survival free of neurosensory disability. RESULTS: Of the 1059 eligible long-term survivors, 963 (91%) were included in the primary outcome; 479 (91%) in the repeat corticosteroid group and 484 (91%) in the placebo group. The rate of survival free of neurosensory disability was similar in both groups (78.3% repeat versus 77.3% placebo; risk ratio 1.00, 95% confidence interval, 0.94–1.08). Neurodevelopment, including cognitive function, and behavior, body size, blood pressure, spirometry, and health-related quality of life were similar in both groups, as was the use of health services. CONCLUSIONS: Treatment with repeat dose(s) of antenatal corticosteroids was associated with neither benefit nor harm in mid-childhood. Our finding of long-term safety supports the use of repeat dose(s) of antenatal corticosteroids, in view of the related neonatal benefits. For women at risk for preterm birth before 32 weeks’ gestation, ≥7 days after an initial course of antenatal corticosteroids, clinicians could consider using a single injection of betamethasone, repeated weekly if risk remains.

Ultrafast x-ray scattering studies of the topological Skyrmion phase in Cu_{2}OSeO_{3} show the dynamics to be strongly dependent on the excitation energy and fluence. At high photon energies, where the electron-spin scattering cross section is relatively high, the excitation of the topological Skyrmion phase shows a nonlinear dependence on the excitation fluence, in contrast to the excitation of the conical phase which is linearly dependent on the excitation fluence. The excitation of the Skyrmion order parameter is nonlinear in the magnetic excitation resulting from scattering during electron-hole recombination, indicating different dominant scattering processes in the conical and Skyrmion phases.

A group is called a generalized Baumslag–Solitar group , or GBS-group , if it is the fundamental group of a graph of groups with infinite cyclic vertex and edge groups. A GBS-group is said to be GBS-simple if it has no proper, non-cyclic geometric quotients, i.e., quotients other than Z which arise from geometric homomorphisms. The main result gives a complete description of the GBS-groups which are GBS-simple. This is achieved by constructing a set of natural examples of geometric homomorphisms.

We extend to FC ⁎ , the class of generalized FC-groups introduced in [F. de Giovanni, A. Russo, G. Vincenzi, Groups with restricted conjugacy classes, Serdica Math. J. 28 (2002) 241–254], some results known for FC-groups. The main theorem involves the extended residually finite property (ERF), i.e., all subgroups are closed in the profinite topology. The ERF-groups belonging to several large classes of groups have been determined, for example nilpotent groups [M. Menth, Nilpotent groups with every quotient residually finite, J. Group Theory 5 (2002) 199–217] and FC-groups [D.J.S. Robinson, A. Russo, G. Vincenzi, On groups whose subgroups are closed in the profinite topology, J. Pure Appl. Algebra 213 (2009) 421–429]. Here we generalize these results by classifying completely the ERF-groups belonging to FC ⁎ .

A theorem is established which describes the structure of locally finite groups in whose finite subgroups Sylow permutability is a transitive relation.

Please cite this paper as: Dodd J, Grivell R, Crowther C, Robinson J. Antenatal interventions for overweight or obese pregnant women: a systematic review of randomised trials. BJOG 2010;117:1316–1326. Background Overweight and obesity during pregnancy is an increasing health problem. Objective A systematic review to assess the benefits and harms of antenatal dietary or lifestyle interventions for pregnant women who are overweight or obese. Search strategy The Cochrane Controlled Trials Register (CENTRAL) was searched (last search January 2010). Reference lists of retrieved studies were searched by hand. No date or language restrictions were used. Selection criteria Randomised controlled trials comparing antenatal dietary and/or lifestyle or other interventions with no treatment for overweight or obese women were considered. Studies were evaluated independently for appropriateness for inclusion and methodological quality. The primary outcome was large-for-gestational-age infants. Data collection and analysis Nine randomised controlled trials were included involving 743 women who were overweight or obese during pregnancy. Seven trials compared a dietary intervention with standard antenatal care. Main results There were no statistically significant differences identified between women who received an antenatal intervention and those who did not for the large-for-gestational-age infant outcome (three studies; 366 women; risk ratio 2.02; 95% CI 0.84, 4.86) or mean gestational weight gain [four studies; 416 women; weighted mean difference −3.10 kg; 95% CI −8.32, 2.13 (random-effects model)]. There were no statistically significant differences identified for other reported outcomes. Author’s conclusions The effect of providing an antenatal dietary intervention for overweight or obese pregnant women on maternal and infant health outcomes remains unclear.

Being born small due to poor growth before birth increases the risk of developing metabolic disease, including type 2 diabetes, in later life. Inadequate insulin secretion and decreasing insulin sensitivity contribute to this increased diabetes risk. Impaired placental growth, development and function are major causes of impaired fetal growth and development and therefore of IUGR. Restricted placental growth (PR) and function in non-human animals induces similar changes in insulin secretion and sensitivity as in human IUGR, making these valuable tools to investigate the underlying mechanisms and to test interventions to prevent or ameliorate the risk of disease after IUGR. Epigenetic changes induced by an adverse fetal environment are strongly implicated as causes of later impaired insulin action. These have been well-characterised in the PR rat, where impaired insulin secretion is linked to epigenetic changes at the Pdx-1 promotor and reduced expression of this transcription factor. Present research is particularly focussed on developing intervention strategies to prevent or reverse epigenetic changes, and normalise gene expression and insulin action after PR, in order to translate this to treatments to improve outcomes in human IUGR.

We have investigated the effects of restriction of placental growth on foetal adrenal growth and adrenal expression of mRNAs for Insulin-like Growth Factor II (IGF-II), the IGF binding protein IGFBP-2, Steroidogenic Factor 1 (SF-1) and adrenocorticotrophic hormone (ACTH) receptor (ACTH-R) and the steroidogenic cytochrome P-450 enzymes: cholesterol side chain cleavage (CYP11A1), 17alpha-hydroxylase (CYP17) and 21-hydroxylase (CYP21A1); and 3beta-hydroxysteroid dehydrogenase/Delta5Delta4 isomerase (3betaHSD). Endometrial caruncles were removed from non-pregnant ewes before mating (placental restriction group; PR). The total adrenal: foetal weight ratio was higher in PR (n=6 foetuses) than in control foetuses (n=6 foetuses). There was no difference in plasma ACTH concentrations between the PR and control foetuses between 130 and 140 days gestation. Adrenal IGF-II mRNA levels were lower (P

A group is called HNN-free if it has no subgroups that are nontrivial HNN-extensions. We prove that finitely generated HNN-free implies virtually polycyclic for a large class of groups. We also consider finitely generated groups with no free subsemigroups of rank 2 and show that in many situations such groups are virtually nilpotent. Finally, as an application of our results, we determine the structure of locally graded groups in which every subgroup is pronormal, thus generalizing a theorem of Kuzennyi and Subbotin.

A new technique for probing the structural rearrangements of molecules following ionization has recently been demonstrated. Whilst straightforward to implement, this technique offers remarkable time resolution, allowing intramolecular nuclear dynamics to be followed with a precision of 100 as. Here we discuss this technique, termed PACER (probing attosecond dynamics by chirp encoded recollision), examine the processes that affect the measurement, and compare the technique to alternative methods for probing vibrational wavepackets in light molecules.

Objective To evaluate the effect of providing antenatal dietary and lifestyle advice on neonatal anthropometry, and to determine the inter-observer variability in obtaining anthropometric measurements. Design Randomised controlled trial. Setting Public maternity hospitals across metropolitan Adelaide, South Australia. Population Pregnant women with a singleton gestation between 10+0 and 20+0 weeks, and body mass index (BMI) ≥25 kg/m2. Methods Women were randomised to either Lifestyle Advice (comprehensive dietary and lifestyle intervention over the course of pregnancy including dietary, exercise and behavioural strategies, delivered by a research dietician and research assistants) or continued Standard Care. Analyses were conducted using intention-to-treat principles. Main outcome measures Secondary outcome measures for the trial included assessment of infant body composition using body circumference and skinfold thickness measurements (SFTM), percentage body fat, and bio-impedance analysis of fat-free mass. Results Anthropometric measurements were obtained from 970 neonates (488 Lifestyle Advice Group, and 482 Standard Care Group). In 394 of these neonates (215 Lifestyle Advice Group, and 179 Standard Care Group) bio-impedance analysis was also obtained. There were no statistically significant differences identified between those neonates born to women receiving Lifestyle Advice and those receiving Standard Care, in terms of body circumference measures, SFTM, percentage body fat, fat mass, or fat-free mass. The intra-class correlation coefficient for SFTM was moderate to excellent (0.55–0.88). Conclusions Among neonates born to women who are overweight or obese, anthropometric measures of body composition were not modified by an antenatal dietary and lifestyle intervention. Tweetable abstract Lifestyle advice in pregnancy does not modify body composition of infants of overweight and obese women.

The cysteine protease calpain-I is linked to several diseases and is therefore a valuable target for inhibition. Selective inhibition of calpain-I has proved difficult as most compounds target the active site and inhibit a broad spectrum of cysteine proteases as well as other calpain isoforms. Selective inhibitors might not only be potential drugs but should act as tools to explore the physiological and pathophysiological roles of calpain-I. α-Mercaptoacrylic acid based calpain inhibitors are potent, cell permeable and selective inhibitors of calpain-I and calpain-II. These inhibitors target the calcium binding domain PEF(S) of calpain-I and -II. Here X-ray diffraction analysis of co-crystals of PEF(S) revealed that the disulfide form of an α-mercaptoacrylic acid bound within a hydrophobic groove that is also targeted by a calpastatin inhibitory region and made a greater number of favourable interactions with the protein than the reduced sulfhydryl form. Measurement of the inhibitory potency of the α-mercaptoacrylic acids and X-ray crystallography revealed that the IC50 values decreased significantly on oxidation as a consequence of the stereo-electronic properties of disulfide bonds that restrict rotation around the S–S bond. Consequently, thioether analogues inhibited calpain-I with potencies similar to those of the free sulfhydryl forms of α-mercaptoacrylic acids.

In recent years the use of high-order harmonic radiation to create and control events on attosecond timescales has grown at a phenomenal rate. With the use of carrier-envelope phase (CEP) stabilization and few-cycle laser systems it is possible to probe physical processes on unprecedented timescales. Here, we report the first experimental observation of high-harmonic emission at individual half-cycles of a laser pulse. We show that these half-cycle emissions are extremely sensitive to the CEP, providing a route to a new single-shot measurement technique of the CEP. We use this technique to measure the CEP of an 8.5 fs pulse at a centre wavelength of 800 nm with an accuracy of 20 as (1 as=1×10−18 s). With appropriate spatio-spectral filtering of the harmonic spectra, our calculations show that we can isolate emission from an individual half-cycle cutoff, which corresponds to a single isolated attosecond pulse of duration

We have investigated experimentally the energy transmission and spectral broadening of 30-fs, 700-μJ laser pulses in a neon-filled, 250-μm inner diameter hollow fibre. We implement a differentially pumped fibre, where a vacuum is maintained at the fibre entrance, and compare this to a statically filled fibre. We obtain significantly higher transmission and increased spectral broadening in the differentially pumped case due to a reduction of ionisation defocusing at the fibre entrance. This arrangement provides a method for the generation of near-transform- limited pulses with smoothly varying pulse duration whilst maintaining constant pulse energy, by simple adjustment of the gas pressure. Compression of ∼450-μJ pulses from the differentially pumped fibre to a duration of 6.5 fs has been achieved for pulses with spectra spanning 650–900 nm, by use of negatively dispersive chirped mirrors.

The Maier–Schmid theorem asserts that a core-free permutable subgroup of a finite group is contained in the hypercentre. This result is known to be false even for finitely generated groups. Here it is shown that the Maier–Schmid theorem holds for many classes of infinite groups, including numerous locally finite groups. On the other hand, an example is given of a countable metabelian p-group for which the theorem fails.

Anatomical hemispherectomy is frequently employed in the surgical management of pediatric patients with medically refractory epilepsy.In this chapter, we review the historical evolution of this surgical procedure, outline the indications and the criteria for selecting surgical candidates and describe the important pre-operative evaluation of the surgical candidates.We provide a detailed description of our surgical technique, anesthesiological considerations, and post-operative care plan. Ultimately we analyze the most common complications associated with this procedure.Anatomical hemispherectomy performed in carefully selected pediatric patients with medically intractable epilepsy can be a safe and efficacious surgical procedure.

A study is made of groups with finitely many derived groups of subgroups or of infinite subgroups. These groups are classified completely in the locally graded case. In the general case, detailed structural information about groups in each class is found.

Evidence is accumulating that the risk of osteoporosis in later life may be determined in part by environmental influences on bone development during intrauterine and early postnatal life. A potential role for fetal leptin in mediating these effects is suggested by animal studies showing that leptin influences prenatal osteoblast growth and development, and that fetal leptin concentrations are altered by changes in maternal nutrition. In a group of term human infants we reported previously that maternal birthweight, smoking, fat mass, and exercise during late pregnancy independently predict neonatal bone mass. To investigate the potential role of leptin in mediating these effects, we now relate leptin concentrations in umbilical venous serum to neonatal bone mass and body composition in 117 infants. There were strong positive associations between umbilical venous leptin concentration and each of whole body bone mineral contents (BMC) (r = 0.42, P < or = 0.001) and estimated volumetric bone density (r = 0.21, P = 0.02); whole body lean mass (r = 0.21, P < or = 0.024); and whole body fat mass (r = 0.60, P < 0.001). The associations with neonatal BMC and fat mass, but not with lean mass, were independent of associations that we have reported previously between cord serum insulin-like growth factor 1 (IGF-1) concentrations and neonatal body composition. Among the maternal determinants of neonatal bone mass, cord leptin explained the relationship with maternal fat stores, but not those with the mother's own birthweight, smoking, or physical activity. We conclude that umbilical venous leptin predicts both the size of the neonatal skeleton and its estimated volumetric mineral density. In addition, among previously documented maternal determinants of neonatal bone mass in healthy pregnancies, maternal fat stores may mediate their effect on fetal bone accrual through variation in fetal leptin concentrations.

Finite groups in which each cyclic subnormal subgroup is Sylow-permutable, permutable or normal are investigated. Characterizations are found in both the soluble and insoluble cases.

We study the structure of groups that satisfy the maximal conditions on infinite normal subgroups and the minimal condition on normal subgroups of infinite index. Characterizations of both properties are given in the general case. In addition, detailed information is obtained about the structure of soluble groups that satisfy these chain conditions.