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Scalable fabrication concepts of 3D kidney tissue models are required to enable their application in pharmaceutical high-throughput screenings. Yet the reconstruction of complex tissue structures remains technologically challenging. We present a novel concept reducing the fabrication demands, by using controlled cellular self-assembly to achieve higher tissue complexities from significantly simplified construct designs. We used drop-on-demand bioprinting to fabricate locally confined patterns of renal epithelial cells embedded in a hydrogel matrix. These patterns provide defined local cell densities (cell count variance µm in diameter (size variance µm). These showed a continuous lumen with prescribed orientation, lined by an epithelial monolayer with tight junctions. Additionally, upregulated expression of kidney-specific functional genes compared to 2D cell monolayers indicated increased tissue functionality, as revealed by mRNA sequencing. Furthermore, our concept enabled the fabrication of hybrid tubules, which consisted of arranged subsections of different cell types, combining murine and human epithelial cells. Finally, we integrated the self-assembled fabrication into a microfluidic chip and achieved fluidic access to the lumen at the terminal sites of the tubules. With this, we realized flow conditions with a wall shear stress of 0.05 ± 0.02 dyne cm−2 driven by hydrostatic pressure for scalable dynamic culture towards a nephron-on-chip model.

A correlated analysis of observables arising from loop induced effects from a vectorlike generation is given. The observables include flavor changing radiative decays $\mu\to e \gamma, \tau\to \mu \gamma, \tau\to e \gamma$, electric dipole moments of the charged leptons $e,\mu, \tau$, and corrections to magnetic dipole moments of $g_\mu-2$ and $g_e-2$. In this work we give a full analysis of the corrections to these observables by taking into account both the supersymmetry loops as well as the exchange of a vectorlike leptonic generation. Thus the fermion mass matrix involves a $5\times 5$ mixing matrix while the scalar sector involves a $10\times 10$ mixing matrix including the CP violating phases from the vectorlike sector. The analysis is done under the constraint of the Higgs boson mass at the experimentally measured value. The loops considered include the exchange of $W$ and $Z$ bosons and of leptons and a mirror lepton, and the exchange of charginos and neutralinos, sleptons and mirror sleptons. The correction to the diphoton decay of the Higgs $h\to \gamma\gamma$ including the exchange of the vectorlike leptonic multiplet is also computed., Comment: 34 pages, 8 figures (Accepted for publication in PRD)

In the standard model flavor violating decays of the top quark and of the Higgs boson are highly suppressed. Further, the flavor violating decays of the top and of the Higgs are also small in MSSM and not observable in current or in near future experiment. In this work we show that much larger branching ratios for these decays can be achieved in an extended MSSM model with an additional vector like quark generation. Specifically we show that in the extended model one can achieve branching ratios for $t\to h^0 c$ and $t\to h^0 u$ as large as the current experimental upper limits given by the ATLAS and the CMS Collaborations. We also analyze the flavor violating quark decay of the Higgs boson, i.e., $h^0\to b\bar s + \bar b s$ and $h^0\to b\bar d + \bar b d$. Here again one finds that the branching ratio for these decays can be as large as $O(1)\%$. The analysis is done with inclusion of the CP phases in the Higgs sector, and the effect of CP phases on the branching ratios is investigated. Specifically the Higgs sector spectrum and mixings are computed involving quarks and mirror quarks, squarks and mirror squarks in the loops consistent with the Higgs boson mass constraint. The resulting effective Lagrangian with inclusion of the vector like quark generation induce flavor violating decays at the tree level. The test of the branching ratios predicted could come with further data from LHC13 and such branching ratios could also be accessible at future colliders such as the Higgs factories where the Higgs couplings to fermions will be determined with greater precision., 26 pages. 8 figures

Recent data from the ATLAS and CMS detectors at the Large Hadron Collider at CERN give a hint of possible violation of flavor in the leptonic decays of the Higgs boson. In this work we analyze the flavor violating leptonic decays $H^0_1\to l_i \bar l_j$ ($i\neq j$) within the framework of an MSSM extension with a vectorlike leptonic generation. Specifically we focus on the decay mode $H^0_1\to \mu\tau$. The analysis is done including tree and loop contributions involving exchange of $W, Z$, charge and neutral higgs and leptons and mirror leptons, charginos and neutralinos and sleptons and mirror sleptons. It is found that a substantial branching ratio of $H^0_1\to \mu\tau$, i.e., of as much a ${\cal{O}}(1)\%$, can be achieved in this model, the size hinted by the ATLAS and CMS data. The flavor violating decays $H^0_1\to e\mu, e\tau$ are also analyzed and found to be consistent with the current experimental limits. An analysis of the dependence of flavor violating decays on CP phases is given. The analysis is extended to include flavor decays of the heavier Higgs bosons. A confirmation of the flavor violation in Higgs boson decays with more data that is expected from LHC at $\sqrt s=13$ TeV will be evidence of new physics beyond the standard model., Comment: 33 pages, 13 figures. Accepted for publication in PRD

Background and Objectives: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure that has a well-established role in the diagnosis and staging of lung cancer. This technology is also widely used for the diagnosis of mediastinal masses and cysts as well as other inflammatory disorders such as sarcoidosis. However, the utility of this procedure in the diagnosis and subclassification of lymphoproliferative disorders (LPDs) is not clear. We performed a systematic review to evaluate EBUS-TBNA use in LPDs. Materials and Methods: PubMed, EMBASE, MEDLINE, Cochrane Library Plus, and ISI Web of Knowledge were searched for studies of clinical trials in English reporting diagnostic performance of EBUS-TBNA in lymphoma until September 2014. The overall sensitivity, negative predictive value (NPV), and diagnostic accuracy were evaluated. Results: Six trials involving 346 patients with suspected lymphoma were included. The overall sensitivity, NPV, and diagnostic accuracy ranged 38%-91%, 83%-96.4%, and 91%-97%, respectively. Further invasive surgery was needed only in 13-43% of the patients. None of the studies included in the present review reported important complications. Conclusion: Current evidence suggests that EBUS-TBNA can be used as an initial evaluation for patients with suspected lymphoma. Additional surgical procedures may be necessary if a sample is inadequate or negative with high suspicion of lymphoma. Further multicenter trials are needed to evaluate the diagnostic yield of EBUS-TBNA in lymphoma patients.

An innovative concept using energy dissipating devices, such as buckling restrained braces (BRB), is proposed for special truss moment frames (STMF). The configuration of the proposed system consists of pins introduced at the ends of the top and bottom chord elements of the special segments. Subsequently, energy dissipating devices are used in the form of diagonal braces inside the special segments. An energy-based design methodology is adopted such that the BRBs are designed to provide sufficient energy dissipation capacity with respect to seismic input energy demand on the structure. This energy-based methodology is demonstrated to be accurate by means of a series of nonlinear time-history analyses. The overall seismic response of the proposed system is contrasted with the conventional STMF in terms of story displacements, interstory drifts, story shears and overturning moments, as well as observed damage to structural elements. The proposed system leads to more predictable seismic response and would potentially allow lighter construction and significant cost savings, due to significantly reduced member forces (up to 50% compared with conventional design). Furthermore, damage to structural elements is largely mitigated, hence allowing damage avoidance design of STMFs.

An analysis is given of the decay $\ensuremath{\mu}\ensuremath{\rightarrow}e+\ensuremath{\gamma}$ in an minimal supersymmetric standard model extension with a vectorlike generation. Here mixing with the mirrors allows the possibility of this decay. The analysis is done at the one-loop level with the exchange of charginos and neutralinos and of sleptons and mirror sleptons in the loops. A one-loop analysis with W- and Z-boson exchange and mirror leptons and neutrinos is also considered. The effects of $CP$-violating phases from the new sector on the decay $\ensuremath{\mu}\ensuremath{\rightarrow}e\ensuremath{\gamma}$ are analyzed in detail. The constraints arising from the current upper limit on the branching ratio $\mathcal{B}(\ensuremath{\mu}\ensuremath{\rightarrow}e\ensuremath{\gamma})$ from the MEG experiment of $2.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}$ (at 90% C.L.) on the parameter space of supersymmetry (SUSY) models and on vectorlike models are explored. Further, the MEG experiment is likely to improve the upper limit by an order of magnitude in the coming years. The improved limits will allow one to probe a much larger domain of the parameter space of the extended models.

We give a quantitative analysis of the electric dipole moments as a probe of high scale physics. We focus on the electric dipole moment of the electron since the limit on it is the most stringent. Further, theoretical computations of it are free of QCD uncertainties. The analysis presented here first explores the probe of high scales via electron electric dipole moment (EDM) within minimal supersymmetric standard model where the contributions to the EDM arise from the chargino and the neutralino exchanges in loops. Here it is shown that the electron EDM can probe mass scales from tens of TeV into the PeV range. The analysis is then extended to include a vectorlike generation which can mix with the three ordinary generations. Here new $CP$ phases arise and it is shown that the electron EDM now has not only a supersymmetric (SUSY) contribution from the exchange of charginos and neutralinos but also a nonsupersymmetric contribution from the exchange of $W$ and $Z$ bosons. It is further shown that the interference of the supersymmetric and the nonsupersymmetric contribution leads to the remarkable phenomenon where the electron EDM as a function of the slepton mass first falls and become vanishingly small and then rises again as the slepton mass increases. This phenomenon arises as a consequence of cancellation between the SUSY and the non-SUSY contribution at low scales while at high scales the SUSY contribution dies out and the EDM is controlled by the non-SUSY contribution alone. The high mass scales that can be probed by the EDM are far in excess of what accelerators will be able to probe. The sensitivity of the EDM to $CP$ phases both in the SUSY and the non-SUSY sectors are also discussed.

An analysis of the Dirac neutrino magnetic moment with standard model interactions gives $\mu_\nu\sim 3 \times 10^{-19} \mu_B (m_\nu/1 eV)$. The observation of a significantly larger magnetic moment will provide a clear signal of new physics beyond the standard model. The current experimental limits on the neutrino magnetic moments are orders of magnitude larger than the prediction with the standard model interactions and thus its test appears out of reach. Here we give an analysis of the Dirac neutrino magnetic moments within the framework of a minimal supersymmetric standard model extension with a vectorlike lepton generation. Specifically we compute the moments arising from the exchange of W and the charged leptons in the loop, as well as from the exchange of charginos, charged sleptons and charged mirror sleptons. It is shown that the neutrino moment in this case can be several orders of magnitude larger than the one with standard model like interactions, lying close to and below the current experimental upper limits and should be accessible in improved future experiment. A correlated prediction of the heaviest neutrino lifetimes from radiative decays to the lighter neutrinos via exchange of charginos and sleptons in the loops is also made. The predicted lifetimes are several orders of magnitudes smaller than the one with the standard model interactions and also lie close to the current experimental limits from analyses using the cosmic background neutrino data., Comment: 23 pages, 8 figures. arXiv admin note: text overlap with arXiv:1306.2275. Accepted for publication in PRD