204,918 research outputs found
Dr. Jess M. Bader, circa 1930
No full textA portrait of Dr. Jesse M. Bader. Written on recto: Dr. Jesse M. Bade
Some remarks on flocks
No full textNew proofs are given of the fundamental results of Bader,
Lunardon and Thas relating flocks of the quadratic
cone in pg(3,q), q odd, and BLT-sets of Q(4,q). We also
show that there is a unique BLT-set of H(3,9). The model of
Penttila for Q(4,q) q odd, is extended to
Q(2m,q) to construct partial flocks of size qm/2+m/2-1 of the
cone K in pg(2m-1,q) with vertex a point and base
Q(2m-2,q) , where q is congruent to 1 or 3 modulo 8 and m
is even. These
partial flocks are larger than the largest previously known
for m>2 . Also, the
example of O'Keefe and Thas of a partial
flock of K in pg(5,3) of size 6 is generalised to a
partial flock of the cone K of pg(2pn-1,p) of size 2pn , for any prime p congruent to 1 or 3 modulo 8,
with the corresponding partial BLT-set of
Q(2pn,p) admitting the symmetric group of degree 2pn+1
The legacy of Ruth Bader Ginsburg
No full textL’Autrice approfondisce il personaggio ed il ruolo di Justice Ruth Bader Ginsburg secondo la prospettiva del diritto costituzionale nazionale.
Il saggio ripercorre la storia di Justice Ginsburg, occupandosi prima del suo contributo come avvocata e successivamente come giudice presso la Corte Suprema statunitense.
Attraverso l’analisi di alcune tra le sue opinions più importanti, sia di maggioranza che dissenzienti, il saggio offre un affresco del pensiero di Justice Ginsburg su alcune tematiche fondamentali sotto il profilo dei diritti e dei rapporti tra Giudice costituzionale e legislatore.
In particolare, l’A. si sofferma sulla concezione di eguaglianza promossa da Justice Ginsburg soprattutto, ma non solo, in relazione ai diritti delle donne e con riferimento al concetto di azione positiva; segue, poi, un approfondimento delle funzioni del dissent nel sistema istituzionale statunitense e un’analisi della nozione di giustizia come interpretata da Justice Ginsburg.
Il saggio si propone, quindi, di evidenziare l’eredità che Justice Ginsburg ha lasciato dietro di sè a livello globale.The Author investigates the figure and role of Justice Ruth Bader Ginsburg from a constitutional law perspective.
The paper deals with contribution of Justice Ruth Bader Ginsburg as a lawyer first and later as justice appointed to the United States Supreme Court.
By way of analysis touching upon some her most prominent majority and dissenting opinions, the A. hinges on several issues pertaining to the safeguard of fundamental rights and to the relationships between the legislator and the Constitutional Judge.
The Author then goes on by examining Justice Ginsburg’s concept of equality with respect to women’s rights and affirmative actions to then move on to an in depth focus on the role of the dissent in the US legal system and on Justice Ginsburg’s concept of justice.
At the outset, the Articles aims at highlighting the legacy of Ruth Bader Ginsburg on a global dimension
Biomechanical signals and the C-type natriuretic peptide counteract catabolic activities induced by IL-1? in chondrocyte/agarose constructs
No full textIntroduction: The present study examined the effect of C-type natriuretic peptide (CNP) on the anabolic and catabolic activities in chondrocyte/agarose constructs subjected to dynamic compression. Methods: Constructs were cultured under free-swelling conditions or subjected to dynamic compression with low (0.1 to 100 pM) or high concentrations (1 to 1,000 nM) of CNP, interleukin-1? (IL-1?), and/or KT-5823 (inhibits cyclic GMP-dependent protein kinase II (PKGII)). Anabolic and catabolic activities were assessed as follows: nitric oxide (NO) and prostaglandin E2 (PGE2) release, and [3H]-thymidine and 35SO4 incorporation were quantified by using biochemical assays. Gene expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), aggrecan, and collagen type II were assessed with real-time quantitative PCR (qPCR). Two-way ANOVA and the post hoc Bonferroni-corrected t tests were used to examine data. Results: CNP reduced NO and PGE2 release and partially restored [3H]-thymidine and 35SO4 incorporation in constructs cultured with IL-1?. The response was dependent on the concentration of CNP, such that 100 pM increased [3H]-thymidine incorporation (P < 0.001). This is in contrast to 35SO4 incorporation, which was enhanced with 100 or 1000 nM CNP in the presence and absence of IL-1? (P < 0.001). Stimulation by both dynamic compression and CNP and/or the PKGII inhibitor further reduced NO and PGE2 release and restored [3H]-thymidine and 35SO4 incorporation. In the presence and absence of IL-1?, the magnitude of stimulation for [3H]-thymidine and 35SO4 incorporation by dynamic compression was dependent on the concentration of CNP and the response was inhibited with the PKGII inhibitor. In addition, stimulation by CNP and/or dynamic compression reduced IL-1?-induced iNOS and COX-2 expression and restored aggrecan and collagen type II expression. The catabolic response was not further influenced with the PKGII inhibitor in IL-1?-treated constructs. Conclusions: Treatment with CNP and dynamic compression increased anabolic activities and blocked catabolic effects induced by IL-1?. The anabolic response was PKGII mediated and raises important questions about the molecular mechanisms of CNP with mechanical signals in cartilage. Therapeutic agents like CNP could be administered in conjunction with controlled exercise therapy to slow the OA disease progression and to repair damaged cartilage. The findings from this research provide the potential for developing novel agents to slow the pathophysiologic mechanisms and to treat OA in the young and old. <br/
Unionicola cooki Bader 1981
No full textUnionicola cooki Bader, 1981 New records. Ghana. 0/1/0, Inlet Volta River at Kpong, 6°09.183′ N 0°03.709′ E, 25 m a.s.l., 10 Mar. 2011. Distribution. Cameroon (Bader 1981, Smit 1994), Ivory Coast (Hevers 2010), Ghana (this study).Published as part of Smit, Harry, 2021, Water mites from West Africa (Acari: Hydrachnidia), pp. 700-746 in Acarologia 61 (3) on page 734, DOI: 10.24349/5d6U-DX5N, http://zenodo.org/record/715954
Viscoelastic Cell Mechanics and actin remodelling are dependent on the rate of applied pressure
No full textBackground: living cells are subjected to external and internal mechanical stresses. The effects of these stresses on the deformation and subsequent biological response of the cells remains unclear. This study tested the hypothesis that the rate at which pressure (or stress) is applied influence the viscoelastic properties of the cell associated with differences in the dynamics of the actin cytoskeleton.Principal finding: micropipette aspiration was used to determine the instantaneous and equilibrium moduli and the viscosity of isolated chondrocytes based on the standard linear solid (SLS) model and a variation of this incorporating Boltzmann superposition. Cells were visualised for 180 seconds following aspiration to 7 cmH2O at 0.35, 0.70 and 5.48 cmH2O/sec. Cell recovery was then examined for a further 180 seconds once the pressure had been removed. Reducing the rate of application of pressure reduced the levels of cell deformation and recovery associated with a significant increase in modulus and viscosity. Using GFP transfection and confocal microscopy, we show that chondrocyte deformation involves distortion, disassembly and subsequent reassembly of the cortical actin cytoskeleton. At faster pressure rates, cell deformation produced an increase in cell volume associated with membrane bleb formation. GFP-actin transfection inhibited the pressure rate dependent variation in cell mechanics indicating that this behaviour is regulated by GFP-sensitive actin dynamics.Conclusion: we suggest that slower rates of aspiration pressure enable greater levels of cortical actin distortion. This is partially inhibited by GFP or faster aspiration rates leading to membrane bleb formation and an increase in cell volume. Thus the rate of application of pressure regulates the viscoelastic mechanical properties of living cells through pressure rate sensitive differences in actin dynamics. Therefore cells appear softer when aspirated at a faster rate in contrast to what is expected of a normal viscoelastic materia
Stem cell mechanobiology
No full textStem cells are undifferentiated cells that are capable of proliferation, self-maintenance and differentiation towards specific cell phenotypes. These processes are controlled by a variety of cues including physicochemical factors associated with the specific mechanical environment in which the cells reside. The control of stem cell biology through mechanical factors remains poorly understood and is the focus of the developing field of mechanobiology. This review provides an insight into the current knowledge of the role of mechanical forces in the induction of differentiation of stem cells. While the details associated with individual studies are complex and typically associated with the stem cell type studied and model system adopted, certain key themes emerge. First, the differentiation process affects the mechanical properties of the cells and of specific subcellular components. Secondly, that stem cells are able to detect and respond to alterations in the stiffness of their surrounding microenvironment via induction of lineage-specific differentiation. Finally, the application of external mechanical forces to stem cells, transduced through a variety of mechanisms, can initiate and drive differentiation processes. The coalescence of these three key concepts permit the introduction of a new theory for the maintenance of stem cells and alternatively their differentiation via the concept of a stem cell 'mechano-niche', defined as a specific combination of cell mechanical properties, extracellular matrix stiffness and external mechanical cues conducive to the maintenance of the stem cell population.<br/
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