Category: Nevin Manimala

Rep Prog Phys. 2023 Jan 16. doi: 10.1088/1361-6633/acb36e. Online ahead of print.

ABSTRACT

Many experimentally relevant quantum spin chains are approximately integrable, and support long-lived quasiparticle excitations. A canonical example of integrable model of quantum magnetism is the XXZ spin chain, for which energy spreads ballistically, but, surprisingly, high-temperature spin transport can be diffusive or superdiffusive. We review the transport properties of this model using an intuitive quasiparticle picture that relies on the recently introduced framework of generalized hydrodynamics. We discuss how anomalous linear response properties emerge from hierarchies of quasiparticles both in integrable and near-integrable limits, with an emphasis on the role of hydrodynamic fluctuations. We also comment on recent developments including non-linear response, full-counting statistics and far-fromequilibrium transport. We provide an overview of recent numerical and experimental results on transport in XXZ spin chains.

PMID:36645909 | DOI:10.1088/1361-6633/acb36e

Biomed Phys Eng Express. 2023 Jan 16. doi: 10.1088/2057-1976/acb357. Online ahead of print.

ABSTRACT

We propose a technique for metal artefact reduction in digital tomosynthesis reconstruction. Although the problem was addressed earlier in the literature, we suggest another approach, which is, in our opinion, simpler, and easier to implement. It is a two-stage algorithm. At the first stage, attenuation images are segmented by decomposing their intensity distributions into gaussian-like components. Statistical information contained in each component is used for pixel classification. Components corresponding to metallic objects are identified, and a pixel threshold value separating regions occupied by metal objects from the rest of the image is found. Based on this value, at the second stage, a smooth mapping of image intensity is applied. This makes dense regions transparent, resulting in the artefact reduction in reconstruction. The methodology is demonstrated by several examples.

PMID:36645907 | DOI:10.1088/2057-1976/acb357

Ann Intern Med. 2023 Jan 17. doi: 10.7326/M22-0364. Online ahead of print.

ABSTRACT

BACKGROUND: Primary infection with or reactivation of Epstein-Barr virus (EBV) can occur after liver transplant (LT) and can lead to posttransplant lymphoproliferative disease (PTLD). In pediatric LT, an EBV-DNA viral load (EBV VL) monitoring strategy, including the reduction of immunosuppression, has led to a lower incidence of PTLD. For adult LT recipients with less primary infection and more EBV reactivation, it is unknown whether this strategy is effective.

OBJECTIVE: To examine the effect of an EBV VL monitoring strategy on the incidence of PTLD after LT in adults.

DESIGN: Cohort study.

SETTING: Two university medical centers in the Netherlands.

PATIENTS: Adult recipients of first LT in Leiden between September 2003 and January 2017 with an EBV VL monitoring strategy formed the monitoring group (M1), recipients of first LT in Rotterdam between January 2003 and January 2017 without such a strategy formed the contemporary control group (C1), and those who had transplants in Leiden between September 1992 and September 2003 or Rotterdam between 1986 and January 2003 formed the historical control groups (M0 and C0, respectively).

MEASUREMENTS: Influence of EBV VL monitoring on incidence of PTLD.

RESULTS: After inverse probability of treatment weighting of the 4 groups to achieve a balance among the groups for important patient characteristics, differences within hospitals between the historical and recent era in cumulative incidences-expressed as the number of events per 1000 patients measured at 5-, 10-, and 15-year follow-up-showed fewer events in the contemporary era in both centers. This difference was considerably larger in the monitoring center, whereas the 95% CI included the null value of 0 for point estimates.

LIMITATION: Retrospective, low statistical power, and incompletely balanced groups, and non-EBV PTLD cannot be prevented.

CONCLUSION: Monitoring EBV VL may reduce PTLD incidence after LT in adults; larger studies are warranted.

PRIMARY FUNDING SOURCE: None.

PMID:36645888 | DOI:10.7326/M22-0364

Am J Speech Lang Pathol. 2023 Jan 16:1-24. doi: 10.1044/2022_AJSLP-22-00101. Online ahead of print.

ABSTRACT

PURPOSE: A mixed-method approach was used to investigate the lived experiences of adults with mild traumatic brain injury (mTBI). The study aimed to understand the perceived relationship between cognitive-communication problems, thinking and communication concerns, and neurobehavioral symptoms. We hypothesized that individuals with cognitive-communication problems would attribute their problems with communication to their mTBI history and their self-perceived problems would be correlated with symptomatology.

METHOD: The Neurobehavioral Symptom Inventory (NSI) and an online cognitive-communication survey was used to conduct a study of 30 adults with mTBI history. Quantitative survey and NSI scores were analyzed with content analysis and correlational statistics.

RESULTS: The average NSI Total score was 17 with the following subscale scores: somatic (5), affective (8), and cognitive (3.9). Participants reported problems with expressive communication (56%), comprehension (80%), thinking (63%), and social skills (60%). Content analysis revealed problems in the following areas: expression (e.g., verbal, and written language), comprehension (reading and verbal comprehension), cognition (e.g., attention, memory and speed of processing, error regulation), and functional consequences (e.g., academic work, social problems, and anxiety and stress). A Pearson correlation indicated a statistically significant relationship (p < .01) between the Communication Survey Total and the Total, Somatic, Affective, and Cognitive subscales.

CONCLUSIONS: This study highlights a multifactorial basis of cognitive-communication impairment in adults with mTBI. We show that those with mTBI history perceive difficulties with cognitive-communication skills: conversations, writing, and short-term memory/attention. Furthermore, those with mTBI perceive their cognitive-communication problems after injury have impacted their vocational, social, and academic success.

PMID:36645876 | DOI:10.1044/2022_AJSLP-22-00101

Aggress Behav. 2023 Jan 16. doi: 10.1002/ab.22070. Online ahead of print.

ABSTRACT

We conducted an observational study of a collection of interactive processes known as “demand-withdraw” in relation to adolescent dating aggression. Couples (N = 209) aged 14-18 years participated in a challenging observational laboratory assessment to measure demands (i.e., pressures for a change), as well as demand → partner withdraw and demand → partner avoid sequences. Actor and partner effects were disentangled via dyadic data analyses. The results indicated a fairly consistent pattern in which demand → withdraw and demand → avoid sequences led by either partner were positively associated with both partners’ physical and psychological aggression (measured via a dual informant questionnaire method). Further, higher quality demands (i.e., pressures for change that were specific and encouraged both members of the dyad to increase a given behavior) were inversely associated with aggression. Yet, all of the above associations were attenuated to the point of statistical nonsignificance after controlling for hostility. These results suggest two primary possibilities. The associations of demand → withdraw and demand → avoid sequences with dating aggression may be spurious, with the sequences merely markers for hostility, a known correlate of dating aggression. Alternatively, hostility may mediate the relations of demand → withdraw and demand → avoid sequences with dating aggression. Further research is required to test these competing explanations. Implications for preventive intervention are discussed.

PMID:36645870 | DOI:10.1002/ab.22070

Int J Prosthodont. 2022 Nov-Dec;35(6):815-823. doi: 10.11607/ijp.7986.

ABSTRACT

PURPOSE: To evaluate the long-term survival of IPS Empress 2 and IPS e.max (Ivoclar Vivadent) restorations in a non-university setting.

MATERIALS AND METHODS: A retrospective study design was used to evaluate the survival rate of 1,132 Empress 2 and IPS e.max restorations placed in 251 patients with regard to patient age, gender, tooth type, tooth vitality, material, restoration form (inlay vs partial crown vs crown), cementation mode (self-adhesive vs non-self-adhesive), and bruxism activity. Kaplan-Meier and regression analyses were used for statistical analyses.

RESULTS: Of the 1,132 restorations, a total of 15 (IPS e.max = 3, Empress 2 = 12) failed. The overall survival rate for all restorations was 98.7% after 15.4 years. A significantly reduced survival rate was found for nonvital teeth (P = .002), patient age > 60 years (P = .002), crowns (vs inlays and partial crowns; P = .002), and self-adhesive resin materials (P = .018).

CONCLUSION: Within the limitations of this study, glass-ceramic single-tooth restorations made of Empress 2 and IPS e.max show good survival rates up to a period of 15 years.

PMID:36645866 | DOI:10.11607/ijp.7986

Int J Prosthodont. 2022 Nov-Dec;35(6):752-760. doi: 10.11607/ijp.7302.

ABSTRACT

PURPOSE: To evaluate the effects of nonthermal atmospheric plasma (NTAP) treatment, alone or combined with sandblasting and/or primer application, on the bonding of zirconia ceramics to resin cement. Materıals and Methods: A total of 420 discs of Y-TZP (2 x 15 x 12 mm) were prepared and randomly divided into 10 groups according to surface treatment, as follows: Z (control), SB (sandblasting), Pr (primer), SBPr (sandblasting + primer), P (NTAP), SBP (sandblasting + NTAP), PrP (primer + NTAP), SBPrP (sandblasting + primer + NTAP), PPr (NTAP + primer), and SBPPr (sandblasting + NTAP + primer). After surface treatments, the surface roughness values were evaluated using a profilometer, and the contact angle measurements were performed using a goniometer. Surface characterizations of the groups were analyzed using scanning electron microscopy and x-ray photoelectron spectroscopy analyses. Shear bond strength tests were performed after adhesive cementation in 20 specimens per group, with half (n = 10) subjected to thermocycling (5,000 cycles, 5°C to 55°C). The failure mode was recorded by examining each specimen using a stereomicroscope. One-way and two-way ANOVA followed by Student-Newman-Keuls test (α = .05) were used to analyze the data statistically.

RESULTS: Untreated zirconia surfaces (without sandblasting) were found to have a higher wettability and oxygen ratio after NTAP treatment. The clinical application order of NTAP is an important factor, and the best combination for bonding quality was NTAP treatment followed by primer application on untreated zirconia (group PPr), rather than on a sandblasted surface. Conclusıon: NTAP application may be a promising surface treatment method for adhesive cementation of zirconia ceramics as an alternative to sandblasting. To achieve strong adhesion, NTAP should be applied before primer aplication.

PMID:36645863 | DOI:10.11607/ijp.7302

Int J Prosthodont. 2022 Nov-Dec;35(6):724-729. doi: 10.11607/ijp.7825.

ABSTRACT

PURPOSE: To evaluate correlations of arch size and sex with the interocclusal rest distance (IORD), as well as to estimate proportional variance.

MATERIALS AND METHODS: A total of 106 participants were examined. The participants, 38 men and 68 women, were aged 22 to 30 years, were fully dentate, had no signs of abnormal abrasion, and had intact posterior occlusal contacts. Measurements of interocclusal rest distance and tragus-incisal distance were recorded, and the rest angle created between the tragus-incisal distance in maximum intercuspation and in resting vertical dimension were calculated according to the cosine formula. Correlation between the size of the mandible (tragus-incisal distance, mean of left and right sides) and the IORD were calculated using Pearson correlation coefficient. Correlations for sex (calculated separately for male and female) and rest angle were also assessed.

RESULTS: The mean (SD) tragus-incisal distance values were 123.38 (6.77) mm for all participants, 120.01 (4.64) mm for women, and 130.72 (5.24) mm for men. The mean (SD) IORD values were 2.76 (1.3) mm for all participants, 2.13 (0.9) mm for women, and 3.87 (1.17) mm for men. The mean (SD) rest angle values were 1.26 (0.55) degrees for all participants, 1.02 (0.41) degrees for women, and 1.7 (0.49) degrees for men. Pearson correlation coefficient between IORD and tragus-incisal distance was significant (P < .05). According to t test, there was a significant difference between men and women for IORD, tragus-incisal distance, and rest angle (P < .01).

CONCLUSION: A correlation exists between IORD and arch size. A statistically significant difference was found between men and women for IORD and arch size values.

PMID:36645862 | DOI:10.11607/ijp.7825

Int J Prosthodont. 2022 Nov-Dec;35(6):718-723. doi: 10.11607/ijp.8053.

ABSTRACT

PURPOSE: To compare predoctoral student performance in restorative dentistry related to curricular changes implemented in response to the COVID-19 pandemic and to evaluate the impact of remote education on performance in didactic and preclinical examinations and objective structured clinical examinations (OSCEs).

MATERIALS AND METHODS: The study population consisted of 172 students, all members of the DMD graduating classes from 2017 to 2021. Scores in the Final Restorative Treatment (FRTx) course, subdivided into didactic and preclinical lab work, and the OSCEs were assessed and compared between pre-pandemic students and during-pandemic students.

RESULTS: Performance in the preclinical lab exercises was statistically significantly higher in the during-pandemic cohort than in the pre-pandemic cohort after adjusting for students’ gender and admission scores. Performance in restorative dentistry as measured by the OSCE was not statistically different among during-pandemic students compared to the pre-pandemic students. It was observed that students were more efficient and engaged during the more limited lab sessions with the increased student-to-faculty ratio that allowed for more feedback.

CONCLUSION: Although virtual education cannot replace in-person experiences, this model served students satisfactorily during the COVID-19 pandemic, with added support structures such as flexible scheduling, interactive sessions, and additional small-group discussions to maintain academic performance in predoctoral education.

PMID:36645861 | DOI:10.11607/ijp.8053

JMIR Form Res. 2023 Jan 3. doi: 10.2196/34128. Online ahead of print.

ABSTRACT

BACKGROUND: In March 14, 2020, the state of alarm and was declared in Spain due to the spread of the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2). Beyond this date, the coronavirus disease 2019 (COVID-19) in the country changed the practice of oncologic care.

OBJECTIVE: Since recurrent hospital visits were potential risk factors for contagion, the aims of this prospective observational study was to analyze the consequences of COVID-19 pandemic in the health care of patients with lymphoma.

METHODS: All data were obtained from the electronic medical record (EMR). Variables such as age, sex, matter of the visit, use of patient’s portal, changes in management, impact in clinical trials and suffering from COVID-19 contagion were recorded.

RESULTS: 290 patients were attended in the lymphoma clinic accomplishing 437 appointments. The median age was 66 years (range 18-94) and 157 (54.13%) were male. Of them, 214 patients (73.79%) had only 1 visit to the clinic. Only 23 patients (7.93%) didn’t have access to patient’s portal. Amid the COVID-19 pandemic, 78 patients (26.89%) remained in active treatment, 35 patients (12.06%) suffered from delayed in their treatments and 6 patients (2.06%) suffered from treatment discontinuation. During the follow-up, only 8 patients (2.75%) suffered from COVID-19 (7 cases with confirmed PCR test and 1 case with clinical suspicion). Despite the implementation of telemedicine strategies to avoid visit to hospital, 66 patients (22.75%) had in-person visits to the lymphoma clinic. Patients who attended in-person consultation were younger than those who preferred telemedicine consultation (62 vs 66 years) and had less use of patient’s portal (7.58% vs 9%), although these differences didn’t reach statistical significance. Patients who atttended in-person visits used to have only 1 visit to hospital (43.93% vs 82.58%, P<.0001). Regarding the matter of in-person consultation, more patients were on active treatment in comparison with those using telemedicine resources (56.06% vs 18.30%, P<.0001). Patients with preference for telemedicine strategies had more surveillance visits (65.62% vs 36.36%, P<.0001). With regards of treatment modifications, more treatment delays (12.94% vs 9.09%) and more definite treatment discontinuations (2.67% vs 0%) were seen in patients using telemedicine resources when compared to patients attending in-person visits, although these differences didn’t reach statistical significance. Regarding the type of therapy, patients attending in-person visits were more likely to receive an intravenous treatment rather than those on telemedicine (62.16% vs 40.47%, P<.0001).

CONCLUSIONS: Telemedicine such as patient’s portal are feasible strategies in the management of patients with lymphoma during the COVID-19 pandemic, with a reduction of in-person visits to hospital and a very low contagion rate.

PMID:36645838 | DOI:10.2196/34128