Point Junction Research Articles

Angulation, contact point, and cementoenamel junction distance of impacted mandibular third molars referred for extraction are probably associated with distal caries in the second molar

Angulation, contact point, and cementoenamel junction distance of impacted mandibular third molars referred for extraction are probably associated with distal caries in the second molar

Minimisation of electric field stress at triple junction of a functionally graded cone type spacer in a gas insulated busduct with metal inserts

Insulation integrity of supporting insulator plays a vital role for determining the continuity of service of the gas insulated substation which depends upon the electric field stress distribution on the surface of the spacer. Triple junction formed by the conductor, SF6 gas and support insulator is another critical area where the field stress is to be maintained at minimum value. Shape control is a technique employed for obtaining uniform field stress along the surface of the spacer but this technique may sometimes leads to very uneven shapes. In this study, a functional graded material is designed for the standard cone type spacer to obtain uniform field stress along the surface of spacer to overcome the above problem. The grading of spacer is done with different permittivities. Electric field is computed for three cases namely grading to high, grading to low and U Shape. The metal inserts were tuned and stress is obtained in account of lower fields at the triple point junction and an improved uniform field distribution along the surface is obtained.

The presence of extra chromosomes leads to genomic instability.

Aneuploidy is a hallmark of cancer and underlies genetic disorders characterized by severe developmental defects, yet the molecular mechanisms explaining its effects on cellular physiology remain elusive. Here we show, using a series of human cells with defined aneuploid karyotypes, that gain of a single chromosome increases genomic instability. Next-generation sequencing and SNP-array analysis reveal accumulation of chromosomal rearrangements in aneuploids, with break point junction patterns suggestive of replication defects. Trisomic and tetrasomic cells also show increased DNA damage and sensitivity to replication stress. Strikingly, we find that aneuploidy-induced genomic instability can be explained by the reduced expression of the replicative helicase MCM2-7. Accordingly, restoring near-wild-type levels of chromatin-bound MCM helicase partly rescues the genomic instability phenotypes. Thus, gain of chromosomes triggers replication stress, thereby promoting genomic instability and possibly contributing to tumorigenesis.

Study in Step by Step Electric Energy Meter Connection Detection Method

Electric energy meter wiring error variety, detection method and circuit can only detect some kinds of wrong wiring at present, as the current transformer and current detection unit terminal short-circuit characteristics of conventional methods in existence, not take out stitches under the premise of not achieving detection. Based on this, this paper puts forward a step detection method, detection circuit of voltage and current lines one by one through right off and polarity of current, gradually show every junction point junction and the fault point. Through the Multisim software simulation, and developed a set of wire detecting device, simulation and experimental results prove that the method is correct. Compared with conventional methods, can be more comprehensive and faster connection detection fault location. DOI: http://dx.doi.org/10.11591/telkomnika.v14i1.7662

Void Detection in Dielectric Films Using a Floating Network of Substrate-Embedded Electrodes

A sensor is developed for simple, in situ characterization of dielectric thermal interface materials (TIMs) at bond line thicknesses less than 100 μm. The working principle is based on the detection of regions of contrasting electric permittivity. An array of long, parallel electrodes is flush-mounted into each opposing substrate face of a narrow gap interface, and exposed to the gap formed between the two surfaces. Electrodes are oriented such that their lengthwise dimension in one substrate runs perpendicular to those in the other. A capacitance measurement taken between opposing electrodes is used to characterize the interface region in the vicinity of their crossing point (junction). The electric field associated with each electrode junction is numerically simulated and analyzed. Criteria are developed for the design of electrode junction geometries that localize the electric fields. The capacitances between floating-ground electrodes in the electrode sensor configuration employed give rise to a nontrivial network of interacting capacitances which strongly influence the measured response at any junction. A generalized solution for analyzing the floating network response is presented. The technique is used to experimentally detect thermal grease spots of 0.2 mm to 1.8 mm diameter within a 25 μm interface gap. It is necessary to use the generalized solution to the capacitance network developed in this work to properly delineate regions of contrasting permittivity in the interface gap region using capacitance measurements.

Colonoscopy Preparation-Related Ischemic Colitis Presenting as a Colonic Mass

Purpose: The incidence of ischemic colitis is estimated to be 4.5 to 44 cases per 100,000 person-years. Patients typically present with painful diarrhea followed by hematochezia. This case report highlights an unusual presentation of ischemic colitis presenting with an obstructing mass mimicking colon cancer. A 66-year-old overweight female with 50 pack-years of tobacco use and chronic obstructive pulmonary disease presented as an outpatient with a change in bowel habit and hematochezia. The patient presented to the ER with diffuse severe abdominal pain and rectal bleeding following standard preparation for colonoscopy with polyethylene glycol solution. On examination her pulse was 118/min and tenderness was present in left lower quadrant without rebound tenderness, guarding, or rigidity. The WBC count was 14,000/uL, hemoglobin was 13.4 gm/dL, and MCV was 84.3. A CT scan showed proctosigmoiditis with segmental dilatation of the descending colon. A colonoscopy showed a 12-cm-long partially obstructing rectosigmoid mass starting 12 cm from anal verge. Above the mass erythema, edema, friability, ulceration, and surface hemorrhage were present. As a result it was difficult to delineate the proximal border of the mass. Multiple diverticula were seen in right colon. Biopsies of the mass showed small vessel vascular proliferation with hyaline thrombi suggestive of ischemic changes. In view of the endoscopic findings, which were highly suspicious for malignancy, a repeat colonoscopy was performed. Repeat biopsies showed hyalinized blood vessels with fibrinoid necrosis. The patient's symptoms did not improve with fluid resuscitation and antibiotics. Consequently, an exploratory laparotomy, left colon resection, proctectomy, and end colostomy with Hartmann's pouch were performed. At the time of surgery good pulses were noted in inferior mesenteric vessels. The final pathology confirmed ischemic colitis; there was no evidence of malignancy. A hypercoaguable workup was performed and was negative. Griffith's spot (splenic flexure) and Sudeck's point (junction of sigmoid colon and rectum) where collaterals converge are the areas most susceptible to ischemic injury. Ischemic injury can occur in other segments of the colon. Hyalinization of lamina propria, atrophic microcrypts, and transmural fibrosis are pathognomonic features of ischemic colitis. Edematous, hemorrhagic, or necrotic mucosa is seen in acute phase, while strictures or loss of haustrations can be found in the chronic phase. The finding of the mass is uncommon in patients with ischemic disease. This clinical vignette illustrates that patients with ischemic colitis may present with mass lesions in the chronic phase.

Cryptic NUP98/NSD1 Translocations Are Highly Prevalent in FLT3/ITD-Positive Acute Myeloid Leukemia and Lead to High Rate of Induction Failure. Report From Children's Oncology Group

AbstractAbstract ▪529▪This icon denotes a clinically relevant abstractThe nucleoporins (NUP) are a family of proteins, which form the building blocks of the nuclear pore complex. Translocations involving NUP family members NUP214 and NUP98 have been reported in acute myeloid leukemia (AML). DEK/NUP214 (also known as DEK/CAN, t(6;9)) is a known translocation in AML that is highly associated with FLT3/ITD and adverse outcome (see presentation by Moraleda P. et al). By Whole Transcript Sequencing (RNA Seq) we identified 2 cases of NUP98/NSD1 fusions by patients with cytogenetically normal (CN-) AML, both with FLT3/ITD. Recent studies by Hollink I. et al demonstrated high prevalence of FLT3/ITD in patients with NUP98/NSD1 translocations and its association with adverse outcome. Given the significant overlap between DEK/NUP214, NUP98/NSD1 fusions and FLT3/ITD, we studied the prevalence of these fusion transcripts in patients with FLT3/ITD to define the prognostic significance of genomic alteration and their contribution to clinical outcome.Pretreatment samples from patients with FLT3/ITD (N=117) as well as those with CN-AML (N=166) treated on COG-AAML0531 underwent evaluation for NUP98/NSD1 fusion transcripts RT-PCR. Fusion transcripts, as well as the break point junction was verified by Sanger sequencing. Presence of NUP98/NSD1 transcript was correlated with disease characteristics and clinical outcome in patients with FLT3/ITD.In patients with FLT3/ITD (N=117) NUP98-NSD1 was detected in 15 patients (13%). Demographics and disease characteristics of FLT3/ITD patients were compared between those with and without NUP98/NSD1. There were no significant differences in the median age (11 vs. 13 years, p=0.19) or blast % (85% vs. 80%, p=0.23) at diagnosis between patients with and without NUP98/NSD1. Mutations in NPM1 and CEBPA were not detected in those with dual FLT3/ITD and NUP98/NSD1; however, WT1 was significantly more common in FLT3/ITD patients with NUP98/NSD1 than in those without it (43% vs. 13%, p=0.01). Complete remission (CR) rates were compared in FLT3/ITD patients with and without NUP98/NSD1. CR rate in those with and without NUP98/NSD1 was 28% vs. 73% (p=0.002). Moreover, FLT3/ITD patients harboring NUP98/NSD1 were also more likely to have post-induction minimal residual disease (MRD) than those without NUP98/NSD1 (75% vs. 40.6%, p=0.03). In addition to patients with NUP98/NSD1, eight additional patients had NUP214/CAN translocation (i.e., t(6;9)), and cumulatively, translocations involving these two NUP genes accounted for 20% of patients with FLT3/ITD. CR rates in FLT3/ITD-positive patients with and without NUP translocations was determined. Those with NUP98 or NUP214 translocations had a CR rate of 40% compared to 74% in those without NUP translocations (p= 0.001).Further, the presence and prognostic significance of NUP98/NSD1 was then evaluated in CN-AML. The prevalence NUP98/NSD1 in this patient population was 7.8%. Of note, seventy-nine percent of the CN-AML patients with NUP98/NSD1 harbored FLT3/ITD as well. The CR rate for CN-AML harboring NUP98/NSD1 was significantly lower than in those without it (50% vs. 79.5%, p=0.03). When analyzing CN-AML patients who harbored both NUP98/NSD1 and FLT3/ITD, only 33% achieved CR, whereas all patients who with NUP98/NSD1 without FLT3/ITD achieved CR.Although the CR rate does not appear to be affected, AML patients with FLT3-ITD have higher relapse rates and therefore inferior outcome. We now show that among patients with FLT3/ITD, those with concurrent NUP fusions have a very low-rate of CR and high post-induction MRD than those without this fusion. The high prevalence of FLT3/ITD among NUP patients is likely not random and it is conceivable that NUP and FLT3/ITD have cooperating functional consequences that lead to a distinct leukemic phenotype and enhanced drug resistance.In conclusion, the presence of NUP in FLT3-ITD patients identifies a distinct subgroup of patients with a very high-rate of induction failure. FLT3-ITD patients should be further categorized according to the presence of NUP to improve risk-stratification of pediatric and young adult AML patients and help clinicians to identify those at very high-risk for induction failure. New therapy strategies are needed for this subgroup of patients with highly resistant disease. Disclosures:Loken:Hematologics, Inc: Employment, Equity Ownership. Pardo:Hematologics Inc: Employment.

RNA-Sequencing Unveils Cryptic Fusions in Patients with Acute Myeloid Leukemia

AbstractAbstract 1278 Introduction:Acute myeloid leukemia (AML) represents a heterogeneous group of malignancies with great variability in response to therapy. In recent years, an increasing list of molecular markers with prognostic significance in AML has been identified; nonetheless, new prognostic markers and therapeutic targets are still needed. The aim of this study was to identify and verify fusion transcripts using RNA-Sequencing (RNA-Seq) that would be otherwise undetectable by conventional karyotyping. Methods:Transcriptome Sequence data is generated by high-throughput short-read RNA-Seq performed for each AML sample on the Illumina HiSeq. Poly(A) RNA is captured with poly(T) magnetic beads, fragmented, copied to cDNA libraries with reverse transcriptase and random primers. Each library is subjected to 50-cycle paired-end sequencing on the Illumina HiSeq at Hudson Alpha. Filtered Fastq files are processed with TopHat-Fusion [Kim2011,Trapnell2009] alignment software to discover cryptic fusions in RNA-Seq data without relying on known, annotated models. This process yielded an average of 20 million alignable reads per sample. Cord blood blast cell transcripts are also processed and serve as normal controls. A series of filtering steps eliminate junctions commonly found to be in error. Filtered junctions found in at least 3 AML samples and no normal controls are retained as AML-associated candidate junctions. Visual curation of candidates is performed using Integrative Genomics Viewer. Candidate fusions were verified by RT-PCR amplification of the AML-associated fusions in the index cases. Fusion transcript product, as well as the break point junction was verified by Sanger sequencing Results:Diagnostic specimens from 70 patients with de novo AML that included patients with normal karyotype (NK, N=31), core-binding factor (CBF) AML (N=33) and other (N=6) were sequenced. Age at diagnosis varied from 10 months to 69 years (Median 12 years). White blood cell count (WBC) and blast percentage were 49×109/L (range, 2.4 to 496×109/L) and 78% (40% to 100%), respectively. Bioinformatic evaluation of the RNA-Seq data revealed 67 high-value novel fusions that were not detected by conventional karyotyping: 54 (80.6%) were intra- and 13 (19.4%) inter-chromosomal junctions. The number of novel translocations varied in different cytogenetic groups, with 22 novel fusions detected in those with NK (16 intra and 6 inter-chromosomal junctions), 37 CBF (32 intra and 5 inter-chromosomal junctions) and 8 in “other” (6 intra and 2 inter-chromosomal junctions). Thirteen novel fusions (19.4%) were found in at least 2 or more screened-patients: two (15.4%) inter- and 11 (84.6%) intra-chromosomal junctions. Median number of fusions identified per patient was 2 (range, 1 to 6).Novel fusions involving PDGFR-β gene were identified in two patients, each with a different translocation partner (G3BP1 and ETV6, which was an intra and inter-chromosomal fusions, respectively). Sequencing of the fusion transcript junctions verified the fusion junctions and demonstrated in frame fusions of G3BP1 and ETV6 to the kinase domain coding region of PDGFR-β, identical junction to that seen in cases of imatinib sensitive idiopathic hypereosinophilic syndrome (IHES). Frequency validation in 100 adult and 100 pediatric cases identified one additional patient with G3BP1-PDGFR-β. Cryptic NUP98/NSD1 was identified and verified in two patients with normal karyotype as well as NUP98/HOXD13 translocation in one patient. Frequency determination of NUP98/NSD1 demonstrated prevalence of 7.8% in patients with NK, and that of 13% in patients with FLT3/ITD. Patients who harbored both NUP98/NSD1 fusion and FLT3/ITD had a dismal remission induction rate (CR rate in FLT3/ITD with and without NUP98/NSD1 was 28% vs. 73%; p=0.002). Conclusion:Our data show the applicability of RNA-Seq as a tool to discover cryptic fusion transcripts in AML. These novel fusions may define new independent prognostic markers and potential therapeutic targets for patients with this highly treatment-resistant disease. Disclosures:No relevant conflicts of interest to declare.

Comparison between different papillary recession classification systems

Background/purposeTraditional classification systems to assess interdental papillary levels are based only on the vertical relationship among the papilla tip, contact point, and cementoenamel junction. However, the width of papilla recession (PR) is highly visible in terms of dental esthetics. A new classification system is presented to assess central PR and compare differences between the new system and existing systems. Materials and methodsThecentral papillawas visually assessed in 450 adults using standardized periapical radiographs of the maxillary central incisors. The PR classification system presented here is based on vertical and horizontal dimensions of the PR area. Central PR was classified according to the PR system and the system of Nordland and Tarnow (TC). ResultsNinety individuals who had no PRs were classified as degree 0 according to the classification of both TC and Chang. A total of 330 individuals (73.3%) were classified as TC I (Tarnow), and 46, 89, 16, and 183 participants were classified as PR I, PR II, PR III, and PR IV (Chang). Thirty individuals were classified as TC II, and all were classified as PR IV. ConclusionThis study confirmed a significant correlation between the two existing classification methods. The proposed PR classification system characterizes open embrasures in greater detail than previous systems.

Single n-GaN microwire / p-Silicon thin film heterojunction light-emitting diode

The emission and waveguiding properties of individual GaN microwires as well as devices based on an n-GaN microwire/p-Si (100) junction were studied for relevance in optoelectronics and optical circuits. Pulsed photoluminescence of the GaN microwire excited in the transverse or longitudinal direction demonstrated gain. These n-type GaN microwires were positioned mechanically or by dielectrophoretic force onto pre-patterned electrodes on a p-type Si (100) substrate. Electroluminescence from this p-n point junction was characteristic of a heterostructure light-emitting diode. Additionally, waveguiding was observed along the length of the microwire for light originating from photoluminescence as well as from electroluminescence generated at the p-n junction.

Creep of heat treated silicon nitride with neodymium and yttrium oxides additions

At the present work, samples of silicon nitride with 12 wt% of yttrium/neodymium oxides mixture were formed by gas-pressure sintering. Pos sintering heat treatments in nitrogen with a stepwise temperature variation were performed in some samples. The short term compressive creep tests were undertaken in an argon atmosphere, over a stress range of 50–300 MPa and temperature range of 1200–1400 °C. Values of stress exponents near unity for (i) low temperature testing in all materials and (ii) all temperatures for heat treated samples suggest diffusion accommodation processes, involving ambipolar diffusion of ionic species in the grain boundary phases. Crystallization of the remnant phase during heat treatment in a nitrogen atmosphere gives rise to further formation of new phases in the Nd–Si–O–N system such as Nd 4Si 3O 12 and Nd 2Si 3O 3N 4. A consequence of this crystallization is a significant reduction in stress exponents and creep rates for the heat treated samples. The wedge crack observed after creep testing at specimens in its as-sintered condition may be related to the increased probability of cavitation in the second phase glassy layers at triple point junction.

Phonon interference at self-assembled monolayer interfaces: Molecular dynamics simulations

Using molecular dynamics simulations, we expose phonon interference effects in thermal transports across a self-assembled monolayer (SAM) of alkanethiol molecules covalently bonded to (111) gold substrate and physically bonded to silicon. In particular, we show that the thermal conductance of SAM-Au interface depends on the bonding strength at the SAM-Si interface and that the phonon transmission coefficients show strong and oscillatory dependence on frequency, with oscillatory features diminishing with increasing SAM thickness. To explore the generality of this behavior we analyze a simple model of point junction on a one-dimensional chain using the scattering boundary method.

Quasiparticle doppelgängers

By exploiting the concept of particle-hole duality, one can realize a point junction between integer and fractional quantum Hall phases, which constitutes a crucial building block towards possible applications of the quantum Hall effect.

Electron transport in carbon nanotube-silicon heterodimensional heterojunction array: An experimental investigation

Current-voltage experiments on a highly ordered array of carbon nanotubes interfaced with silicon reveal interesting features arising from the regular array of heterojunctions between one-dimensional (1D) and three-dimensional materials. At high temperature, the vertically aligned and ordered nanotubes behave as an array of point junction contacts to the silicon below, which merge into a planar junction as temperature decreases. This model is further supported by the observation of signature space charge limited conduction, whose origin is attributed to deep levels in the silicon substrate and to the strong field enhancement due to the quasi-1D nanotubes.

Fully-depleted Ge interband tunnel transistor: Modeling and junction formation

Complementary fully-depleted Ge interband-tunneling field-effect transistors (TFETs) and static inverters are modeled to quantify TFET performance relative to Si MOSFETs. SYNOPSYS TCAD is used to compute the two-dimensional electrostatics and determine the tunnel junction electric field. This electric field is used in an analytic expression to compute the tunnel current. The speed and power performance of TFETs are compared with the nMOSFET at the same supply voltage, 0.5 V. For a gate length of 20 nm, Ge tunnel transistors can provide similar speed in comparison to 45-nm-node nMOSFETs (18 nm gate length), but saves more than 2× in power and lowers energy by over 7×. Toward demonstrating these transistors, a process for forming submicron p +n + Ge tunnel junctions has been utilized in which Al-doped p + Ge is regrown on n + Ge, following melt-back of a patterned Al deposition. Transmission electron microscopy (TEM) reveals the regrown film and a contact microstructure consistent with the Al–Ge phase diagram. The low peak-to-valley current ratio (PVR) of devices produced by this growth method is likely a result of point defects or junction doping non-uniformity as TEM suggest no dislocations at the regrown junction. The PVR of these junctions does not improve as the device area is reduced from 100 to 0.1 μm 2, a size smaller than the formation scale for grains in the Al–Ge system.

Notes on parafermionic QFTs with boundary interaction

The main result of these notes is an analytical expression for the partition function of the circular brane model [S.L. Lukyanov, A.B. Zamolodchikov, J. Stat. Mech.: Theor. Exp. (2004) P05003] for arbitrary values of the topological angle. The model has important applications in condensed matter physics. It is related to the dissipative rotator (Ambegaokar–Eckern–Schön) model [V. Ambegaokar, U. Eckern, G. Schön, Phys. Rev. Lett. 48 (1982) 1745] and describes a “weakly blocked” quantum dot with an infinite number of tunneling channels under a finite gate voltage bias. A numerical check of the analytical solution by means of Monte Carlo simulations has been performed recently in [S.L. Lukyanov, P. Werner, J. Stat. Mech.: Theor. Exp. (2006) P11002]. To derive the main result we study the so-called boundary parafermionic sine-Gordon model. The latter is of certain interest to condensed matter applications, namely as a toy model for a point junction in the multichannel quantum wire [P. Fendley, H. Saleur, Phys. Rev. B 60 (1999) 11432].

Design of dedicated seven-port star dividers for sectored circular antenna array feeding

In order to mitigate the multipath propagation problems for high rate wlans such as Hiperlan (5 GHz) [2], we study an approach based on electronic beam steering over 360° in azimuth with the help of circular arrays of monopoles [3]. Design simplicity and size constraints intended for potential low-cost applications on the terminals has led us to favor a beam switching topology, using a single feeding-port [4]. Two competing configurations of the microstrip feeding circuit are presented and their principle of operation is experimentally validated through passive circuit configurations. The power distribution is achieved in the first one with the help of a pseudo-divider based on a modified 7-branch star junction, whose specific advantage is its very small size. Unfortunately, this design does not preserve the circular permutation invariance of the radiation patterns. The second circuit bypasses this problem in achieving a power distribution through a virtual point junction, at the cost of an appreciable increase in the circuit size. Afin de reduire les effets nefastes de la propagation multitrajets pour les reseaux locaux sans fil a haut debit de type Hiperlan (5 GHz) [2], une approche fon-dee sur le pointage electronique sur 360° d’azimut par des antennes sectorisees a base de reseaux circulaires de monopoles [3] est etudiee. Les contraintes de simplicite et d’encombrement imposees par les applications potentielles sur des terminaux a bas couts conduisent a developper une topologie a commutation de diagramme, ne comportant qu’un seul acces d’alimentation. Deux configurations concurrentes du circuit d’excitation microbande sont presentees, et leur principe est valide experimentalement dans des configurations passives. La repartition de puissance est obtenue dans le premier au moyen d’un pseudo-diviseur constitue d’une jonction a sept branches, dont le principal interet est la tres faible dimension. Cependant, il ne preserve pas l’invariance par permutation circulaire des diagrammes de rayonnement. Le second circuit evite cet inconvenient en effectuant une repartition de puissance au moyen d’une jonction ponctuelle virtuelle, au prix de dimensions sensiblement plus importantes.

Regiospecific solid-phase synthesis of branched oligonucleotides. Effect of vicinal 2',5'- (or 2',3'-) and 3',5'-phosphodiester linkages on the formation of hairpin DNA.

A general procedure for the solid-phase regiospecific synthesis of branched oligonucleotides (bNA) analogues using readily available phosphoramidite reagents has been developed. The key feature of this method is use of the solid-phase phosphoramidite procedure to assemble linear oligonucleotide sequences and sequential removal of the phosphate (beta-cyanoethyl or methyl) and silyl protecting groups without detaching the nascent oligonucleotide from the solid support. Conversion of the phosphate backbone into the more stable phosphodiester linkages allows for removal of the 2'-O-tert-butyldimethylsilyl protecting group without cleavage or isomerization at the branch point. This method allows for the formation of branched oligonucleotides with sequences of arbitrary base composition, length, and orientation around the branch point junction, including a "Y"-shaped octadecamer d(TACTA)-rA[2',5'd(GTATGT)]3',5'd(CAAGTT). Studies to explore structural effects in the use of a branched adenosine as replacement for nucleotide loops in duplex and triplex DNA are also described. Branched oligonucleotides of the type rA[2',5'dCndA10-5']3',5'dCndT10-3' and rA[2',5'dCn3',3'dA10-5']3',5'dCnT10-3' form hairpin duplexes with thermal stability comparable to or better than that of one with a natural deoxynucleotide loop.

Temporal oscillations of current tunneling through a point junction

We consider scattering of quantum particles by a potential which includes a delta-function whose amplitude contains a term proportional to the density of particles. This is the simplest model of the single-particle tunneling through an ultrashort junction in the presence of the multiparticle interactions. Solution of the scattering problem in this nonlinear model is non-unique in a certain interval of amplitudes of the incident wave. We demonstrate that the nonlinearity gives rise to an oscillatory instability of the scattering solutions, which has a threshold in the density of particles as well as in the single-particle energy. The instability must manifest itself, generating an ac component in the transmitted current.

Destabilization of the tetrahedral point junction by positive triple junction line energy

Destabilization of the tetrahedral point junction by positive triple junction line energy