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Speculations about future directions

Herbert Kroemer
2003 Journal of Crystal Growth  
Although MBE technology is over a quarter-century old, and has been outstandingly successful in the growth of semiconductor heterostructures, it has a large reserve of as-yet unexplored capabilities left, many of which are likely to play a role in the future evolution of MBE. Developments that can be anticipated are the additions of OMVPE techniques to MBE, for example, for gas etching and surface cleanup. A central problem will be finding MBEcompatible ways to achieve lateral pattern control
more » ... wn to the nanometer scale. Nanoimprint techniques are a good candidate for that. Self-assembled quantum dots will probably give way to lithographically defined quantum dots with much better control over size and placement. Heterostructures of materials other than semiconductors will be increasingly explored, like magnetic and superconducting structures, and may be even organics. r
doi:10.1016/s0022-0248(02)02199-1 fatcat:7i4hyuettzg7bgdrmxeu77i3ry

Nobel Lecture: Quasielectric fields and band offsets: teaching electrons new tricks

Herbert Kroemer
2001 Reviews of Modern Physics  
et al., 1980; Kroemer and Chien, 1981; Kroemer, 1985) .  ...  From Kroemer, 1957c. FIG. 5.  ... 
doi:10.1103/revmodphys.73.783 fatcat:qdfuygsirbc75hsftozkxxuwam

The Thomas precession factor in spin–orbit interaction

Herbert Kroemer
2004 American Journal of Physics  
., Vol. 72, No. 1, January 2004 Herbert Kroemer  ... 
doi:10.1119/1.1615526 fatcat:fuvhihdwkvhdlppcgsv27x3lzy

TFAM is a novel mediator of immunogenic cancer cell death

Minghua Yang, Changfeng Li, Shan Zhu, Lizhi Cao, Guido Kroemer, Herbert Zeh, Daolin Tang, Rui Kang
2018 Oncoimmunology  
Immunogenic cell death (ICD) is a type of cell death that is accompanied by the release of damageassociated molecular patterns (DAMPs) and results in a dead-cell antigen-specific immune response. Here, we report that spautin-1, an inhibitor of ubiquitin-specific peptidases, triggers immunogenic cancer cell death in vitro and in vivo. The anticancer activity of spautin-1 occurs independent of autophagy inhibition, but depends on the intrinsic mitochondrial apoptosis pathway. Spautin-1 causes
more » ... chondrial oxidative injury, which results in JUN transcription factor activation in a JNK-dependent manner. Mechanistically, activation of JUN by spautin-1 leads to apoptosis by upregulation of pro-apoptotic BAD expression. Importantly, the release of TFAM, a mitochondrial DAMP, by apoptotic cells may contribute to spautin-1induced ICD via its action on the receptor AGER. Indeed, cancer cells treated with spautin-1 in vitro were able to elicit an anticancer immune response when inoculated in vivo, in the absence of any adjuvant. This immunogenic effect of spautin-1-treated cancer cells was lost when TFAM or AGER were neutralized by specific antibodies. Altogether, our results suggest that spautin-1 may stimulate an apoptotic pathway that results in ICD, in TFAM-and AGER-dependent fashion.
doi:10.1080/2162402x.2018.1431086 pmid:29872558 pmcid:PMC5980348 fatcat:m7odus3elfavfj5wuhhvt7yzva

On the nature of the negative-conductivity resonance in a superlattice Bloch oscillator [article]

Herbert Kroemer
2000 arXiv   pre-print
The sine-term in (20) may be written as a Fourier-Bessel series (see Appendix B), * kroemer@ece.ucsb.edu 2 1 1 J ,(29)and the parameter η reduces to η = ( )J 1 z ,(30)  ... 
arXiv:cond-mat/0007482v2 fatcat:mz6xtwv6kvfolheg6n5ayr67gm

The family (InAs, GaSb, AlSb) and its heterostructures: a selective review

Herbert Kroemer
2004 Physica. E, Low-Dimensional systems and nanostructures  
Additional details of some of the material presented here can be found in a longer 1999 review by Kroemer and Hu [2] , but even there the coverage is by no means complete.  ...  Kroemer proposed that they are not ordinary point defects, but are Tamm states at the InAs-AlSb interface [19] , inherent to the band structure of that interface. Alternatively, Shen et al.  ... 
doi:10.1016/j.physe.2003.08.003 fatcat:thclhvsnqndfrf7ctag6khjlum

Clockophagy is a novel selective autophagy process favoring ferroptosis

Minghua Yang, Pan Chen, Jiao Liu, Shan Zhu, Guido Kroemer, Daniel J. Klionsky, Michael T. Lotze, Herbert J. Zeh, Rui Kang, Daolin Tang
2019 Science Advances  
Ferroptosis is a form of nonapoptotic regulated cell death driven by iron-dependent lipid peroxidation. Autophagy involves a lysosomal degradation pathway that can either promote or impede cell death. A high level of autophagy has been associated with ferroptosis, but the mechanisms underpinning this relationship are largely elusive. We characterize the contribution of autophagy to ferroptosis in human cancer cell lines and mouse tumor models. We show that "clockophagy," the selective
more » ... n of the core circadian clock protein ARNTL by autophagy, is critical for ferroptosis. We identify SQSTM1 as a cargo receptor responsible for autophagic ARNTL degradation. ARNTL inhibits ferroptosis by repressing the transcription of Egln2, thus activating the prosurvival transcription factor HIF1A. Genetic or pharmacological interventions blocking ARNTL degradation or inhibiting EGLN2 activation diminished, whereas destabilizing HIF1A facilitated, ferroptotic tumor cell death. Thus, our findings reveal a new pathway, initiated by the autophagic removal of ARNTL, that facilitates ferroptosis induction.
doi:10.1126/sciadv.aaw2238 pmid:31355331 pmcid:PMC6656546 fatcat:h3gg34vrifcq3m74ii2ql3xmgu

High-Mobility Group Box 1 Is Essential for Mitochondrial Quality Control

Daolin Tang, Rui Kang, Kristen M. Livesey, Guido Kroemer, Timothy R. Billiar, Bennett Van Houten, Herbert J. Zeh, Michael T. Lotze
2011 Cell Metabolism  
Autophagy (which includes macro-, micro-, and chaperone-mediated autophagy) is an important biological mechanism for the elimination of damaged or obsolete macromolecules and organelles (Kroemer (C) ATP  ... 
doi:10.1016/j.cmet.2011.04.008 pmid:21641551 pmcid:PMC3293110 fatcat:t6qxoxazrfdqrmf6o3o426bjie

cAMP metabolism controls caspase-11 inflammasome activation and pyroptosis in sepsis

Ruochan Chen, Ling Zeng, Shan Zhu, Jiao Liu, Herbert J. Zeh, Guido Kroemer, Haichao Wang, Timothy R. Billiar, Jianxin Jiang, Daolin Tang, Rui Kang
2019 Science Advances  
The ability of cytosolic lipopolysaccharide (LPS) to activate caspase-11–dependent nonclassical inflammasome is intricately controlled to avoid excessive inflammatory responses. However, very little is known about the regulatory role of various metabolic pathways in the control of caspase-11 activation. Here, we demonstrate that l-adrenaline can act on receptor ADRA2B to inhibit the activation of the caspase-11 inflammasome by cytosolic LPS or Escherichia coli infection in macrophages.
more » ... ine–induced cAMP production via the enzyme ADCY4 promotes protein kinase A (PKA) activation, which then blocks the caspase-11–mediated proteolytic maturation of interleukin-1β, gasdermin D (GSDMD) cleavage, and consequent DAMP release. Inhibition of PDE8A-mediated cAMP hydrolysis limits caspase-11 inflammasome activation and pyroptosis in macrophages. Consequently, pharmacological modulation of the ADRA2B-ADCY4-PDE8A-PKA axis, knockout of caspase-11 (Casp11−/−), or Gsdmd inactivation (GsdmdI105N/I105N) similarly protects against LPS-induced lethality in poly(I:C)-primed mice. Our results provide previously unidentified mechanistic insight into immune regulation by cAMP and represent a proof of concept that immunometabolism constitutes a potential therapeutic target in sepsis.
doi:10.1126/sciadv.aav5562 pmid:31131320 pmcid:PMC6531004 fatcat:wtmk6hfbmjd47ljc6boc52w2aa

TMEM173 Drives Lethal Coagulation in Sepsis

Hui Zhang, Ling Zeng, Min Xie, Jiao Liu, Borong Zhou, Runliu Wu, Lizhi Cao, Guido Kroemer, Haichao Wang, Timothy R. Billiar, Herbert J. Zeh, Rui Kang (+3 others)
2020 Cell Host and Microbe  
The discovery of TMEM173/STING-dependent innate immunity has recently provided guidance for the prevention and management of inflammatory disorders. Here, we show that myeloid TMEM173 occupies an essential role in regulating coagulation in bacterial infections through a mechanism independent of type I interferon response. Mechanistically, TMEM173 binding to ITPR1 controls calcium release from the endoplasmic reticulum in macrophages and monocytes. The TMEM173-dependent increase in cytosolic
more » ... ium drives Gasdermin D (GSDMD) cleavage and activation, which triggers the release of F3, the key initiator of blood coagulation. Genetic or pharmacological inhibition of the TMEM173-GSDMD-F3 pathway blocks systemic coagulation and improves animal survival in three models of sepsis (cecal ligation and puncture or bacteremia with Escherichia coli or Streptococcus pneumoniae infection). The upregulation of the TMEM173 pathway correlates with the severity of disseminated intravascular coagulation and mortality in patients with sepsis. Thus, TMEM173 is a key regulator of blood clotting during lethal bacterial infections.
doi:10.1016/j.chom.2020.02.004 pmid:32142632 pmcid:PMC7153529 fatcat:rojpem44cvhffekjc4ua5bhsdy

PDK4 dictates metabolic resistance to ferroptosis by suppressing pyruvate oxidation and fatty acid synthesis

Xinxin Song, Jiao Liu, Feimei Kuang, Xin Chen, Herbert J. Zeh, Rui Kang, Guido Kroemer, Yangchun Xie, Daolin Tang
2021 Cell Reports  
The mouse PDAC cell line KPC was derived from tumors from KPC mice (Pdx1-Cre;K-Ras G12D/+ ;p53 R172H/+ ) and was a gift obtained from Herbert J.  ...  Selleck Chemicals S7840 MAK025 S8615 S7023 IKE MIAPaCa2 Selleck Chemicals ATCC S8877 CRL-1420 Erastin PANC1 Selleck Chemicals ATCC S7242 CCL-1469 RSL3 KPC Selleck Chemicals Southwestern Medical Center) Herbert  ... 
doi:10.1016/j.celrep.2021.108767 pmid:33626342 fatcat:vyqyfunzcrclnhswrnd7y5jwgy

Quasiparticle dynamics in ballistic weak links under weak voltage bias: an elementary treatment

Herbert Kroemer
1999 Superlattices and Microstructures  
. † E-mail: kroemer@ece.ucsb.edu 0749-6036/99/050877 + 13 $30.00/0 c 1999 Academic Press In DL, the authors investigated the Shapiro steps induced, by high-frequency irradiation, in the dc currentvoltage  ... 
doi:10.1006/spmi.1999.0704 fatcat:23uyqgakjbbylcnpvphuutfdsm

The Tumor Suppressor p53 Limits Ferroptosis by Blocking DPP4 Activity

Yangchun Xie, Shan Zhu, Xinxin Song, Xiaofang Sun, Yong Fan, Jinbao Liu, Meizuo Zhong, Hua Yuan, Lin Zhang, Timothy R. Billiar, Michael T. Lotze, Herbert J. Zeh (+3 others)
2017 Cell Reports  
., 2014; Green and Kroemer, 2009; Khoo et al., 2014) . Recent studies have suggested surprising roles for TP53 in tumor suppression independent of cell-cycle arrest and apoptosis (Li et al., 2012) .  ... 
doi:10.1016/j.celrep.2017.07.055 pmid:28813679 fatcat:pwnn3qnoifavjlhyk2wqzy7q4e

2000年度ノーベル物理学賞 : Zhores I . Alferov氏, Herbert Kroemer氏, Jack S. Kilby氏

生駒 俊明
Nihon Butsuri Gakkaishi  
doi:10.11316/butsuri1946.56.1.42 fatcat:kfkqiilp6zhspfnsndyddxthoq

Current-voltage characteristics of semiconductor-coupled superconducting weak links with large electrode separations

Mason Thomas, Hans-Richard Blank, Ki C. Wong, Herbert Kroemer, Evelyn Hu
1998 Physical Review B (Condensed Matter)  
We have studied the current-voltage characteristics of superconducting weak links in which the coupling medium is the 2-D electron gas in InAs-based semiconductor quantum wells, with relatively large (typically 0.5 micron) separations between niobium electrodes. The devices exhibit Josephson-like current-voltage characteristics; however, the falloff of the differential resistance with decreasing temperature is thermally activated, and is orders of magnitude slower than for more conventional
more » ... links. Most unexpectedly, the thermal activation energies are found to be proportional to the width of the device, taken perpendicular to the current flow. This behavior falls outside the range of established theories; we propose that it is a fluctuation effect caused by giant shot noise associated with multiple Andreev reflections. The possibility of non-equilibrium effects is discussed.
doi:10.1103/physrevb.58.11676 fatcat:lcelyohdyreivnfwn2fcikv5ie
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