Does robotic-assisted unicompartmental knee arthroplasty restore native joint line more accurately than with conventional instruments?

The study's primary aim is the restoration of native joint line in patients having robotic-assisted unicondylar knee arthroplasty and conventional unicondylar knee arthroplasty. Literature in the past has demonstrated that reducing the joint line can result in greater failure rates. This is a prospective cohort investigation of patients who had medial UKA between March 2017 and March 2022.All patient's pre-operative and post-operative radiological joint line assessments were examined by two observers by Weber's methods. Robotic-assisted UKA performed with hand-held image-free robots was compared to conventional UKA groups. The distal position of the femoral component was higher in Group B utilizing conventional tools than in Group A employing robotic-assisted UKA. This positional difference was statistically significant. The mean difference among the pre-operative and post-operative joint lines in Group A was 1.6 ± 0.49 (range 0.8 mm-2.4 mm), while it was 2.47 ± 0.51 (range 1.6 mm-3.9 mm) (p 0.005) in Group B. In Group A, a greater percentage of the subjects (64%) attained a femoral component position within two millimeters from the joint line, whereas just 18% in Group B did. When compared with the conventional UKA technique, the meticulous attention to detail and planning for ligament rebalancing when using the robotic-assisted UKA technique not solely enhance surgical precision for implant placing but additionally provides excellent native joint line restoration and balancing. For validation of its longevity and survivability, the cohort must be tracked for a longer period of time.

Crossover from gapped-to-gapless Dirac surface states in magnetic topologicalinsulator MnBi2Te4.

Intrinsic magnetic topological insulators (MTI) host exotic topological phases such as quantized anomalous Hall insulating phase, arising due to the large magnetic exchange gap. However, the interplay of magnetism and topology in these systems in different temperature regimes remains elusive. In this work, we present the logarithmic temperature-dependence of conductivity for sub-100 nm thick exfoliated flakes of MTI MnBi2Te4 in the presence of out-of-plane magnetic fields and extracted the linear slope, κ. We observed a characteristic change, ∆κ ∼ -0.5 in the low-temperature regime, indicating the gapped Dirac surface state according to Lu-Shen theory. We also report the recovery of topological properties in the system via the weak-antilocalization (WAL) effect in the vicinity of antiferromagnetic to paramagnetic transition and in the paramagnetic regime. Hikami-Larkin-Nagaoka (HLN) analysis suggested the presence of topological surface states. Therefore, our study helps in understanding how intrinsic magnetism masks topological properties in an MTI as long as magnetic ordering persists. .

Feed withdrawal influences egg production, egg quality and antioxidant variables in White Leghorn layers reared during the tropical summer season.

1. An experiment was conducted with White Leghorn layers (Babcock BV 300) to optimise the feed withdrawal schedule for egg-laying hens (67 to 80 weeks) reared in open-sided poultry houses during the tropical summer season.2. Four feeding schedules (1. ad libitum access to the layer feed, 2. feed withdrawal from 9 AM-5 PM, 3. 11 AM-5 PM, and 4. 1 PM-5 PM followed by free access to the layer feed) were examined. Each feeding schedule was offered to 12 replicates consisting of 12 layers housed in four adjacent cages (45.7 × 35.6 × 43.2 cm).3. Fasting the layers from 1-5 pm reduced egg production compared to layers fasting from 9 or 11 am. The FI/egg or unit egg mass was highest in layers fasted from 1-5 pm. In the 9 am-5 pm fasted group, the cloacal temperature (CT) increased significantly at 11 am and gradually reduced at 3 pm. In the 1-5 pm fasted group, the CT remained higher at 3 pm and 5 pm.4. The cell-mediated immune response in layers fasted from 9 am or 11 am was higher than those fed ad libitum or 1-5 pm fasted group. Lipid peroxidation was higher in layers 1-5 pm fasted group, and significantly lower LP was found in groups that fasted from 9 am or 11 am. In general, the activities of serum antioxidant enzymes (glutathione peroxidase, glutathione reductase, superoxide dismutase) were higher in layers that fasted from 9 am or 11 am compared to those that had ad libitum feed or fasted from 1-5 pm.5. It was concluded that the feed withdrawal should be initiated during the forenoon (9 AM/11 am-5 pm) for optimum production and to reduce oxidative stress in egg-laying hens reared during summer in the tropical region.

Bulk-surface coupling in dual topological insulator Bi1Te1and Sb-doped Bi1Te1single crystals via electron-phonon interaction.

Recently,Bi1Te1has been proved to be a dual topological insulator (TI), a new subclass of symmetry-protected topological phases, and predicted to be higher order topological insulator (HOTI). Being a dual TI (DTI), Bi1Te1is said to host quasi-1D surface states (SSs) due to weak TI phase and topological crystalline insulating SSs at the same time. On the other hand, HOTI supports topologically protected hinge states. So,Bi1Te1is a unique platform to study the electrical signature of topological SS (TSS) of fundamentally different origins. Though there is a report of magneto-transport measurements on large-scale Bi1Te1thin films, the Bi1Te1single crystal is not studied experimentally to date. Even the doping effect in a DTI Bi1Te1is missing in the literature. In this regard, we performed the perpendicular and parallel field magneto-transport measurement on the exfoliated microflake of Bi1Te1and Sb-doped Bi1Te1single crystals, grown by the modified Bridgmann method. Ourmetallicsample shows the weak anti-localization behavior analyzed by the multi-channel Hikami-Larkin-Nagaoka equation. We observed the presence of a pair of decoupled TSS. Further, we extracted the dephasing index (ß) from temperature (T)-dependence of phase coherence length (Lϕ), following the power law equation (Lϕ∝T-ß). The thickness-dependent value ofßindicates the transition in the dephasing mechanism from electron-electron to electron-phonon interaction with the increase in thickness, indicating the enhancement in the strength of bulk-surface coupling. Sb-doped system shows weakened bulk-surface coupling, hinted by the reduced dephasing indices.

A multilevel electrolyte-gated artificial synapse based on ruthenium-doped cobalt ferrite.

Synaptic devices that emulate synchronized memory and processing are considered the core components of neuromorphic computing systems for the low-power implementation of artificial intelligence. In this regard, electrolyte-gated transistors (EGTs) have gained much scientific attention, having a similar working mechanism as the biological synapses. Moreover, compared to a traditional solid-state gate dielectric, the liquid dielectric has the key advantage of inducing extremely large modulation of carrier density while overcoming the problem of electric pinholes, that typically occurs when using large-area films gated through ultra-thin solid dielectrics. Herein we demonstrate a three-terminal synaptic transistor based on ruthenium-doped cobalt ferrite (CRFO) thin films by electrolyte gating. In the CRFO-based EGT, we have obtained multilevel non-volatile conductance states for analog computing and high-density storage. Furthermore, the proposed synaptic transistor exhibited essential synaptic behavior, including spike amplitude-dependent plasticity, spike duration-dependent plasticity, long-term potentiation, and long-term depression successfully by applying electrical pulses. This study can motivate the development of advanced neuromorphic devices that leverage simultaneous modulation of electrical and magnetic properties in the same device and show a new direction to synaptic electronics.

Probing electron-phonon and phonon-phonon coupling in type-II Dirac semi-metal NiTe2via temperature-dependent Raman spectroscopy.

We report the temperature-dependent structural characterization of type-II Dirac semimetal NiTe2in the form of a bulk single crystal and a nanoflake (200 nm thick). Detailed x-ray diffraction study along with Rietveld refinement analysis reveals superior crystallinity and linear thermal expansion coefficient (αT) of 5.56 × 10-6and 22.5 × 10-6K-1along a or b and c lattice directions, respectively. Temperature evolution of Raman spectra shows non-linear variations in the phonon frequency and full-width half maxima of the out-of-plane A1gand in-plane Egmodes. Raman mode E2g1, corresponding to an in-plane vibration, disappears on decreasing the thickness from bulk to nanoflake. Quantitative analysis with anharmonic model yields dominating electron-phonon interaction over phonon-phonon interaction mediated by three- and four-phonon processes.

Change in surface characteristics and permeability of human enamel after subjecting to radiation therapy.

Background: Radiation-related caries is a complex destructive lesion leading to uncompromising damage of enamel and dentin in patients suffering from head and neck cancer managed with radiotherapy. Aim: The purpose of this study was to evaluate the changes in the permeability of enamel and to assess the morphological and chemical changes of teeth surface subjected to 6 MV photon beam irradiation. Materials and Methods: For this in vitro study, coronal portion of 20 premolars were sectioned mesiodistally into halves and then grouped into two. Samples in group 1 (control) were not subjected to cycles of irradiation and those in group 2 (experimental) were subjected to a cumulative uniform radiation dose of 70 Gray fractioned in 35 fractions with 6 MV photons. The silver nitrate penetration method was used to assess the change in permeability of enamel. The variations in surface topography and mineral content were assessed using scanning electron microscopy with energy dispersive X-ray analysis. Dye penetration scores of surface texture changes were compared between the two groups utilizing the Chi-square test. The change in the elemental levels between enamel surfaces of the two groups was compared using an independent t-test. Results: The application of 6 MV photon radiation did not change enamel permeability and surface topography. However, a noteworthy reduction in the carbon content (P = 0.002) was observed in teeth subjected to irradiation. Conclusions: Though radiation exposure did not alter the enamel permeability and surface topography, it had caused significant chemical compositional changes. Carbon content was significantly reduced in irradiated enamel samples.

Hybridization of long short-term memory with Sparrow Search Optimization model for water quality index prediction.

Water quality (WQ) analysis is a critical stage in water resource management and should be handled immediately in order to control pollutants that could have a negative influence on the ecosystem. The dramatic increase in population, the use of fertilizers and pesticides, and the industrial revolution have resulted in severe effects on the WQ environment. As a result, the prediction of WQ greatly helped to monitor water pollution. Accurate prediction of WQ is the foundation of managing water environments and is of high importance for protecting water environment. WQ data presents in the form of multi-variate time-sequence dataset. It is clear that the accuracy of predicting WQ will be enhanced when the multi-variate relation and time sequence dataset of WQ are fully utilized. This article presents the Water Quality Prediction utilising Sparrow Search Optimization with Hybrid Long Short-Term Memory (WQP-SSHLSTM) model. The presented WQP-SSHLSTM model intends to examine the data and classify WQ into distinct classes. To achieve this, the presented WQP-SSHLSTM model undergoes data scaling process to scale the input data into uniform format. Followed by, a hybrid long short-term memory-deep belief network (LSTM-DBN) technique is employed for the recognition and classification of WQ. Moreover, Sparrow search optimization algorithm (SSOA) is utilized as a hyperparameter optimizer of the proposed DBN-LSTM model. For demonstrating the enhanced outcomes of the presented WQP-SSHLSTM model, a sequence of experiments has been performed and the outcomes are reviewed under distinct prospects. The WQP-SSHLSTM model has achieved 99.84 percent accuracy, which is the maximum attainable. The simulation outcomes ensured the enhanced outcomes of the WQP-SSHLSTM model on recent methods.

Tuning the semimetallic charge transport in the Weyl semimetal candidate Eu2Ir2O7(111) epitaxial thin film with an all-in-all-out spin structure.

We report the stoichiometric epitaxial growth of the Eu2Ir2O7(111) thin film on YSZ substrate by a two-step solid phase epitaxy (SPE) method. An optimized post-annealing environment of the SPE was superior over the conventional air annealing procedure to get rid of the typical impurity phase, Eu2O3. The thickness-dependent structural study on Eu2Ir2O7(111) thin films suggests a systematic control of Ir/Eu stoichiometry in our films, which is otherwise difficult to achieve. In addition, the low-temperature electrical resistivity studies strongly support the claim. The power-law dependence analysis of the resistivity data exhibits a power exponent of 0.52 in 50 nm sample suggesting possible disorder-driven semimetallic charge transport in the 3D Weyl semimetallic (WSM) candidate Eu2Ir2O7. In addition, the all-in-all-out/all-out-all-in antiferromagnetic domains of Ir4+sublattice is verified using the field cooled magnetoresistance measurements at 2 K. Hall resistivity analysis indicate semimetallic hole carrier type dominance near the Fermi level up to the measured temperature range of 2-120 K. Altogether, our study reveals the ground state of stoichiometric Eu2Ir2O7(111) thin film, with an indirect tuning of the off-stoichiometry using thickness of the samples, which is of interest in the search of the predicted 3D WSM phase.

Does Balancing a Total Hip Arthroplasty Require a New Paradigm? Functional 3-Dimensional Balancing in Total Hip Arthroplasty.

BACKGROUND: Traditional principles for successful outcomes in Total Hip Arthroplasty (THA) have relied largely on placing the socket in the native position and trying to restore static anatomical femoral parameters gauged on X-rays or intra-operative measurement. Stability is conventionally achieved by making appropriate changes during the time of trial reduction. Post-operative complications of dislocation and significant Limb Length Discrepancy (LLD) requiring foot wear modification represents opposite ends of the spectrum from a biomechanical perspective and these continue to be relatively high. A move towards giving more importance to functional dynamic parameters rather than static anatomical parameters and less reliance on stability testing at trial reduction is warranted. METHODS: Intraoperative 3D functional balancing of THA without stability testing at trial reduction was practiced in all subjects undergoing THA in our unit from April 2014. To date 1019 patients have had their hips replaced with the same technique. They were followed up till April 2020 for post-operative complications of dislocation and significant LLD needing footwear modification. A secondary cohort of 114 patients from 1st January to December 31st 2017 within this primary group were analyzed clinically and radiologically to ascertain the implications of functional 3D balancing on X-ray parameters, clinical outcome scores (Harris Hip Score and Oxford Hip Score), ability to squat, and subtle subjective post-operative perception of limb lengthening (POPLL). RESULTS: In the primary group of 1019 patients, there were only two dislocations and no patient needed footwear modification for LLD. In the detailed analysis of the secondary cohort of 114 patients, the correlation with restoration of static radiological parameters was inconsistent. 40 patients could not squat and 4 patients had subtle subjective post-operative perceived limb lengthening (POPLL). Measured outcomes such as HHS and OHS were improved in all patients with significant statistical significance (P < 0.001). CONCLUSION: This study underlines the fact that more importance must be given to functional dynamic parameters by 3D balancing of the THA and not on static anatomical X-rays parameters and stability testing during trial reduction. This represents a paradigm shift in the evolution of total hip arthroplasty. LEVEL OF EVIDENCE: A Level II study. (Data collected from the ongoing prospective study) (http://www.spine.org/Documents/LevelsofEvidenceFinal.pdf). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s43465-021-00505-3.

Sources of SARS-CoV-2 and Other Microorganisms in Dental Aerosols.

On March 16, 2020, 198,000 dentists in the United States closed their doors to patients, fueled by concerns that aerosols generated during dental procedures are potential vehicles for transmission of respiratory pathogens through saliva. Our knowledge of these aerosol constituents is sparse and gleaned from case reports and poorly controlled studies. Therefore, we tracked the origins of microbiota in aerosols generated during ultrasonic scaling, implant osteotomy, and restorative procedures by combining reverse transcriptase quantitative polymerase chain reaction (to identify and quantify SARS-CoV-2) and 16S sequencing (to characterize the entire microbiome) with fine-scale enumeration and source tracking. Linear discriminant analysis of Bray-Curtis dissimilarity distances revealed significant class separation between the salivary microbiome and aerosol microbiota deposited on the operator, patient, assistant, or the environment (P < 0.01, analysis of similarities). We also discovered that 78% of the microbiota in condensate could be traced to the dental irrigant, while saliva contributed to a median of 0% of aerosol microbiota. We also identified low copy numbers of SARS-CoV-2 virus in the saliva of several asymptomatic patients but none in aerosols generated from these patients. Together, the bacterial and viral data encourage us to conclude that when infection control measures are used, such as preoperative mouth rinses and intraoral high-volume evacuation, dental treatment is not a factor in increasing the risk for transmission of SARS-CoV-2 in asymptomatic patients and that standard infection control practices are sufficiently capable of protecting personnel and patients from exposure to potential pathogens. This information is of immediate urgency, not only for safe resumption of dental treatment during the ongoing COVID-19 pandemic, but also to inform evidence-based selection of personal protection equipment and infection control practices at a time when resources are stretched and personal protection equipment needs to be prioritized.

Proximate Quantum Spin Liquid on Designer Lattice.

Complementary to bulk synthesis, here we propose a designer lattice with extremely high magnetic frustration and demonstrate the possible realization of a quantum spin liquid state from both experiments and theoretical calculations. In an ultrathin (111) CoCr2O4 slice composed of three triangular and one kagome cation planes, the absence of a spin ordering or freezing transition is demonstrated down to 0.03 K, in the presence of strong antiferromagnetic correlations in the energy scale of 30 K between Co and Cr sublattices, leading to the frustration factor of ∼1000. Persisting spin fluctuations are observed at low temperatures via low-energy muon spin relaxation. Our calculations further demonstrate the emergence of highly degenerate magnetic ground states at the 0 K limit, due to the competition among multiply altered exchange interactions. These results collectively indicate the realization of a proximate quantum spin liquid state on the synthetic lattice.

Does the Femoral Head Size Influence Outcomes After Uncemented Total Hip Arthroplasty for Fused Hips? A Prospective Study in Ankylosing Spondylitis.

BACKGROUND: Uncemented total hip arthroplasty (THA) with large size femoral heads have shown greater advantage with good stability, range of motion and decreased dislocation rate in ankylosing spondylitis (AS). Meticulous planning is needed to address the unique surgical challenges in such patients with fused hip and spinal deformity. MATERIALS AND METHODS: Thirty fivefused hip joints in twenty-five AS patients who underwent uncemented THA (April 2014 to December 2016) were included in our prospective study and were followed up for a minimum period of 36 months. Pain relief, functional improvement and patient satisfaction were statistically assessed using "Visual Analogue Score" (VAS), "Harris Hip Score" (HHS) and "AJRI 10-Point Satisfaction Score" (A10PSS), respectively. RESULTS: The overall mean preoperative VAS improved from 6.9 ± 1.5 to 1.5 ± 1, HHS improved from 50.0 ± 12 to 88.4 ± 7.8 and A10PSS improved from 2.2 ± 1.2 to 7.6 ± 0.8. Our study results were significant with zero dislocation and good functional score in comparison to the other available studies in literature. First subdivision study in AS patients with bilateral THA performed better than unilateral THA. Second subdivision study showed no significant statistical difference in terms of VAS, HHS, A10PSS and dislocation rate in relation to femoral head size between 32 mm, 36 mm and 40 mm. CONCLUSION: Uncemented THA with large size femoral head equal or greater than 32 mm provides better stability and good functional outcome with less dislocation rate in comparison to older studies of literature with femoral head size less than 32 mm. LEVEL OF EVIDENCE: A Level II study. (Data collected from the ongoing prospective study) (https://www.spine.org/Documents/LevelsofEvidenceFinal.pdf).

Subgingival Host-Microbial Interactions in Hyperglycemic Individuals.

Type 2 diabetes mellitus (T2DM) is an established risk factor for periodontitis, yet its contribution to creating host-bacterial disequilibrium in the subgingival crevice is poorly understood. The present investigation aimed to quantify the impact of hyperglycemia on host-bacterial interactions in established periodontitis and to map shifts in these dynamics following mechanical nonsurgical therapy. Seventeen T2DM and 17 non-T2DM subjects with generalized severe chronic periodontitis were recruited along with 20 periodontally healthy individuals. Subjects with periodontitis were treated with scaling and root planing (SRP). Samples of subgingival biofilm and gingival crevicular fluid were collected at baseline and at 1-, 3-, and 6 mo postoperatively. Correlations were generated between 13.7 million 16S ribosomal DNA sequences and 8 immune mediators. Intermicrobial and host-microbial interactions were modeled using differential network analysis. Periodontal health was characterized by a sparse interbacterial and highly connected cytokine-bacterial network, while both normoglycemics and T2DM subjects with periodontitis demonstrated robust congeneric and intergeneric hubs but significantly fewer cytokine-bacterial connections. Following SRP, the cytokine-bacterial edges demonstrated a 2-fold increase 1 mo postoperatively and a 10-fold increase at 6 mo in normoglycemics. In hyperglycemics, there was a doubling at 1 mo but no further changes thereafter. These shifts accompanied an increasingly sparse interbacterial network. In normoglycemics, the nodes anchored by interleukin (IL)-4, IL-6, and IL-10 demonstrated greatest rewiring, while in hyperglycemics, IL-1ß, IL-6, INF-γ, and IL-17 exhibited progressive rewiring. Thus, the present investigation points to a breakdown in host-bacterial mutualism in periodontitis, with interbacterial interactions rather than host-bacterial interactions primarily determining community assembly. Hyperglycemia further exacerbates this uncoupled mutualism. Our data also demonstrate that while nonsurgical therapy might not consistently alter microbial abundances or lower proinflammatory molecules, it "reboots" the interaction between the immunoinflammatory system and the newly colonizing microbiome, restoring a role for the immune system in determining bacterial colonization. However, this outcome is lower and delayed in hyperglycemics.

Dataset on the suitability of groundwater for drinking and irrigation purposes in the Sarabanga River region, Tamil Nadu, India.

The present datasets reveal that to assess the suitability of groundwater quality for drinking and irrigation uses in both Pre and Post Monsoon Season in Sarabanga River region, Tamilnadu, India based on various water quality indices. A total of 50 groundwater samples were collected in different location in a research area. Water Quality Index (WQI) is a number which indicates the suitability of water for drinking purpose. Sodium Absorption Ratio (SAR), Permeability Index (PI), Residual Sodium Carbonate (RSC), Percentage Sodium (%Na), Kelly Ratio (KR) and Magnesium Hazards (MH) are index value which elaborates the fitness of groundwater for agriculture uses. The WQI value for groundwater in both seasons reveals that 74.5 sq.km and 37.24 sq.km of the area were unfit for domestic purposes. Based on irrigation indices, almost all sample locations are suitable for irrigation purposes. The dataset demonstrates how water quality indices would be applied to policymakers to manage, handle and sustainably improve society at large.

Tailoring of uniaxial magnetic anisotropy in Permalloy thin films using nanorippled Si substrates.

In this work the investigation of in-plane uniaxial magnetic anisotropy induced by the morphology due to ion beam erosion of Si(1 0 0) has been done. Ion beam erosion at an oblique angle of incidence generates a well-ordered nanoripple structure on the Si surface and ripple propagates in a direction normal to ion beam erosion. Permalloy thin films grown on such periodic nanopatterns show a strong uniaxial magnetic anisotropy with easy axis of magnetization in a direction normal to the ripple wave vector. The strength of uniaxial magnetic anisotropy is found to be high for the low value of ripple wavelength; it is decreasing with increasing value of ripple wavelength. Similarly, the strength of uniaxial magnetic anisotropy decreases with increasing Permalloy film thickness. Grazing incidence small angle x-ray scattering data reveals an anisotropic growth of Permalloy thin films with preferential orientation of grains in the direction normal to the ripple wave vector. Permalloy thin film growth is highly conformal with the film surface replicating the substrate ripple morphology up to a film thickness of 50 nm has been observed. Correlation between observed uniaxial magnetic anisotropy to surface modification has been addressed.

A comparative study evaluating the role of adductor canal block catheter versus intraarticular analgesic infusion on knee pain and range of motion in the immediate postoperative period: a prospective multicenter trial.

Postoperative pain after total knee arthroplasty (TKA) is an important determinant of hospital stay and rehabilitation and thereby functional outcome. Adductor canal block (ACB) and intraarticular analgesic infiltration through catheters (IAC) are techniques of multimodal analgesia which have shown to control postoperative pain satisfactorily. The aim of this study is to evaluate the efficacy of ACB versus IAC in reducing immediate postoperative pain and thereby allow early rehabilitation. A multicenter quasi-experimental study was conducted on 511 patients undergoing unilateral primary TKA from March 2016 to April 2017 who either received ACB with catheter (Group I, n = 350 patients) or IAC (Group II, n = 172 patients) for postoperative pain control. All the patients were assessed for severity of pain by Visual Analogue Scale at 8, 24, 48, 72 h postoperatively and knee range of motion (ROM) on the day of discharge. There was no significant difference in pain scores on postoperative day (POD) 0 (1.09 ± 0.30 vs. 0.98 ± 0.46, p = 0.45) and POD 1 (1.21 ± 0.45 vs. 1.00 ± 0.00, p = 0.11) and in mean ROM on the day of discharge between ACB and IAC (88.40° ± 7.96° vs. 88.34° ± 5.74°; p = 0.93) groups. This study shows that both ACB and IAC provide satisfactory postoperative analgesia with sparing of quadriceps function and good knee ROM leading to early rehabilitation and reduced hospital with no advantage of one technique over another.

Novel Nicotine Delivery Systems.

Electronic nicotine delivery systems (ENDS) are devices that contain a power source, a heating element, and a tank or cartridge containing an "e-liquid," which is a mixture of nicotine and flavoring in a glycerol-propylene glycol vehicle. Their increasing popularity among adolescents might be attributed to aggressive marketing in physical venues, social media outlets, as well as irreversible changes caused by nicotine in the developing brains of youth and young adults, predisposing them to addictive behaviors. Adolescent ENDS users were 4 times more likely to initiate cigarette smoking, and the odds of quitting smoking were lower and, in many instances, delayed for those using ENDS. ENDS also renormalize cigarette-like behaviors, such as inhaling/exhaling smoke. The oral cavity is the initial point of contact of ENDS and the first affected system in humans. Oral health depends on an intricate balance in the interactions between oral bacteria and the human immune system, and dysbiosis of oral microbial communities underlies the etiology of periodontitis, caries, and oral cancer. Emerging evidence from subjects with periodontitis as well as periodontally healthy subjects demonstrates that e-cigarette use is associated with a compositional and functional shift in the oral microbiome, with an increase in opportunistic pathogens and virulence traits.

Topological insulator n-p-n junctions in a magnetic field.

Electrical transport in three dimensional topological insulators (TIs) occurs through spin-momentum locked topological surface states that enclose an insulating bulk. In the presence of a magnetic field, surface states get quantized into Landau levels giving rise to chiral edge states that are naturally spin-polarized due to spin momentum locking. It has been proposed that p-n junctions of TIs exposed to external magnetic fields can manifest unique spin dependent effects, apart from forming basic building blocks for highly functional spintronic devices. Here, for the first time we study electrostatically defined n-p-n junctions of dual-gated devices of the three dimensional topological insulator BiSbTe1.25Se1.75 in the presence of a strong magnetic field, revealing striking signatures of suppressed or enhanced electrical transport depending upon the chirality of quantum Hall edge states created at the n-p and p-n junction interfaces. Theoretical modeling combining the electrostatics of the dual gated TI n-p-n junction with the Landauer Buttiker formalism for transport through a network of chiral edge states explains our experimental data. Our work not only opens up a route towards exotic spintronic devices but also provides a test bed for investigating the unique signatures of quantum Hall effects in topological insulators.

Restoring Superconductivity in the Quantum Metal Phase of NbSe2 Using Dissipative Coupling.

Localization arguments forbid the appearance of a metallic ground state in two dimensions. Yet, a large variety of disordered superconductors are known to manifest an anomalous metal phase in the zero temperature limit. While previous observations were confined to noncrystalline "dirty" superconductors, the recent observation of the so-called Bose metal phase in crystalline thin flakes of NbSe2 has sparked off intense debate. While the exact nature of this phase remains unknown, it is thought that quantum fluctuations play a decisive role in Bose metal physics. In this work, we study the response of the anomalous metal phase in thin flakes of NbSe2 to dissipative coupling. We evince a dramatic quenching of the Bose metal phase when dissipative coupling is strong, fully restoring a zero resistance superconducting state in the entire region of the magnetic field (H)-temperature (T) phase diagram where the Bose metal phase is otherwise observed. The suppression of the Bose metal phase by dissipative coupling is possible only in a quantum system where dissipation can directly affect system thermodynamics. Our observation of a dissipative phase transition in two-dimensional NbSe2 firmly establishes the quantum nature of the anomalous metal phase in this class of "clean" superconductors.