RESUMEN
Triboelectricity has been a topic of some confusion for many years, probably because it is very diverse and some of the fundamental science has not been clear. This is now starting to change. A few years ago, the importance of flexoelectricity at asperities is pointed out. That paper exploited the established physics of compensation of bound surface or interfacial charges without going into detail. The purpose of this paper is to expand further on this, mapping from the established physics of electrostatics with contact potentials and Maxwell's displacement field to the underlying fundamentals of charge transfer in triboelectricity. Examples from the published literature are used to illustrate this. In the discussion, some of the open questions and challenges to the community are mentioned.
RESUMEN
AIM: The present study explores the treatment need for dental caries in schoolchildren in Herat, Afghanistan. METHODS: A convenience sample of 13 schools were selected for the study. All schools were located in the urban areas near Herat and were selected through allocation by the Ministry of Health, which also approved the study protocol. In the schools, classes were allocated by the principal of the school. All the children in the allocated classes were included in the survey. Data collection was performed in the school setting by trained Afghan dentist examiners. To measure caries experience, DMFT/dmft scores were used, counting the number of decayed (measured at both white spot (D≥1) and cavitation level (D≥3), according to WHO criteria), missing and filled teeth. CONCLUSION: Dental caries is a considerable oral health problem in the study population. The present sample has a high proportion of untreated carious lesions and a very low level of restorative care. Moreover, significant differences were shown in relation to gender and age groups. The present survey results confirm the need for professional operative and preventive oral health care in this region.
Asunto(s)
Caries Dental , Salud Bucal , Niño , Humanos , Estudios Transversales , Caries Dental/epidemiología , Afganistán/epidemiología , Atención Odontológica , Índice CPO , PrevalenciaRESUMEN
BACKGROUND: The European Society of Medical Oncology (ESMO) has suggested using the ESMO-Magnitude of Clinical Benefit Scale (MCBS) to grade the magnitude of clinical benefit of cancer therapies. This approach has not been applied to radiation therapy (RT) yet. We applied the ESMO-MCBS to experiences describing the use of RT to assess (1) the 'scoreability' of the data, (2) evaluate the reasonableness of the grades for clinical benefit and (3) identify potential shortcomings in the current version of the ESMO-MCBS in its applicability to RT. MATERIALS AND METHODS: We applied the ESMO-MCBS v1.1 to a selection of studies in radiotherapy that had been identified as references in the development of American Society for Radiation Oncology (ASTRO) evidence-based guidelines on whole breast radiation. Of the 112 cited references, we identified a subset of 16 studies that are amenable to grading using the ESMO-MCBS. RESULTS: Of the 16 studies reviewed, 3/16 were scoreable with the ESMO tool. Six of 16 studies could not be scored because of shortcomings in the ESMO-MCBS v1.1: (1) in 'non-inferiority studies', there is no credit for improved patient convenience, reduced patient burden or improved cosmesis; (2) in 'superiority studies' evaluating local control as a primary endpoint, there is no credit for the clinical benefit such as reduced need for further interventions. In 7/16 studies, methodological deficiencies in the conduct and reporting were identified. CONCLUSIONS: This study represents a first step in determining the utility of the ESMO-MCBS in the evaluation of clinical benefit in radiotherapy. Important shortcomings were identified that would need to be addressed in developing a version of the ESMO-MCBS that can be robustly applied to radiotherapy treatments. Optimization of the ESMO-MCBS instrument will proceed to enable assessment of value in radiotherapy.
Asunto(s)
Neoplasias de la Mama , Oncología por Radiación , Femenino , Humanos , Neoplasias de la Mama/radioterapia , Oncología Médica , Radioterapia Adyuvante , Sociedades Médicas , Estados Unidos , Guías de Práctica Clínica como AsuntoRESUMEN
Density functional theory calculations use a significant fraction of current supercomputing time. The resources required scale with the problem size, the internal workings of the code, and the number of iterations to convergence, with the latter being controlled by what is called "mixing". This paper describes a new approach to handling trust regions within these and other fixed-point problems. Rather than adjusting the trust region based upon improvement, the prior steps are used to estimate what the parameters and trust regions should be, effectively estimating the optimal Polyak step from the prior history. Detailed results are shown for eight structures using both the "good" and "bad" multisecant versions as well as the Anderson method and a hybrid approach, all with the same predictive method. Additional comparisons are made for 36 cases with a fixed algorithm greed. The predictive method works well independent of which method is used for the candidate step, and it is capable of adapting to different problem types particularly when coupled with the hybrid approach.
RESUMEN
BACKGROUND: There is no well-established gold standard for treating trochanteric femur fractures in the elderly. The two common treatment options are cephalomedullary nails (CMN) and sliding hip screws (SHS). In this study, treatment using CMN and SHS were compared for a cohort of patients older than 70 years of age: The main outcomes were quality of life and main residence after surgery. METHODS: In this retrospective study we analyzed 24,919 patients from 100 hospitals, treated between 2016 and 2019 and documented in the Registry for Geriatric Trauma. The impact of CMN vs. SHS on the walking ability, quality of life (QoL), living situation, mortality, and revision rate were analyzed. To analyze the change of the living situation, the main residence 120 days after surgery for patients, who lived in their own home before fracture, was described for both groups. FINDINGS: A total of 10,995 patients could be included of which 10,436 patients were treated with CMN and 369 patients with SHS. 120 days postoperative the QoL differed significantly (p = 0.020) in favor of treatment using CMN. 26% of the SHS group who lived at home prior to surgery had to reside in a nursing home after surgery, whereas the rate was only 18% in the CMN group (p < 0.001). No significant difference in the mortality rate nor a difference in the walking ability 120 days postoperative were found. CMN were implanted more promptly (median: 13.9 vs. 18.4 hours; p < 0,001). No differences were found concerning the revision rate between the two groups, neither during inpatient treatment (p = 0.723) nor during the 120 day follow-up period (p = 0.524). INTERPRETATION: There might be a benefit for geriatric patients with trochanteric femur fractures to be treated with a proximal femur nail in regard to a higher QoL and a reduced institutionalization rate. Mortality or revision rate was not affected by the chosen implant.
Asunto(s)
Fijación Intramedular de Fracturas , Fracturas de Cadera , Anciano , Clavos Ortopédicos , Tornillos Óseos , Fémur , Fijación Interna de Fracturas , Fracturas de Cadera/cirugía , Humanos , Uñas , Calidad de Vida , Sistema de Registros , Estudios Retrospectivos , CaminataRESUMEN
AIM: To describe parental perceptions of general health, oral health and received dental health care in Swedish children with Down syndrome (DS). METHODS: Online questionnaire, quantitative data analysis (Chi-square test). RESULTS: Parents of 101 children with DS (52 boys, 49 girls, mean age: 9.6 years) participated. Seventy percent rated their child's general health and 74% their child's oral health as good or very good. Parents, who rated their child's oral health as poor (8%), also reported that dental procedures were difficult. Children received dental care at general (55%) and specialist clinics (53%). Ninety-four percent of parents of children receiving specialist dental health care were satisfied compared to 70% of parents with children in general clinics. The parents most valued characteristics of dental professionals were patience (63%) and their ability to engage the child (68%). Parents wanted multidisciplinary collaboration. CONCLUSION: Most parents rated their child's general and oral health as good or very good. Children with poor oral health were also reported to have difficulties coping with dental procedures. Parents wanted dental care to be tailored to meet their child's unique needs. They wanted dental professionals to have knowledge about children with a need for special care. Lastly, they requested multidisciplinary collaboration.
Asunto(s)
Atención Dental para Niños , Síndrome de Down , Niño , Atención a la Salud , Síndrome de Down/terapia , Femenino , Humanos , Masculino , Salud Bucal , Padres , Percepción , SueciaRESUMEN
The value of multi-parametric magnetic resonance imaging in the detection of clinically-significant prostate cancer is increasingly well-established, and has been adopted in current diagnostic pathways and clinical guidelines. Concurrently, the role of conventional ultrasound-guided systematic prostate biopsy is increasingly questioned. In this brief review, we evaluate the continued value of systematic biopsy including a review of prospective studies on targeted and systemic biopsies in the same patients. We also address current limitations of multi-parametric magnetic resonance imaging of the prostate.
Asunto(s)
Biopsia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos , Neoplasias de la Próstata/cirugía , Humanos , Masculino , Estudios Prospectivos , Neoplasias de la Próstata/patologíaRESUMEN
AIM: Determine, whether the UPAT could be used as an extra tool to collect data on functional TMJ pain and to assess orofacial pain levels related to temporomandibular disorder(s) (TMD) in youngsters. METHODS: Patients were screened at the N1 Dental Clinic of Tbilisi State Medical University. The clinical scores of possible functional jaw pain were collected using the UPAT, to indicate pain severity on a visual scale during different jaw movements (opening, closing and lateral). STATISTICS: Comparisons of categorised data have been performed by chi-square test and Fisher's Exact test (where expected values were less than 5). The P value less than 0.05 was considered as statistically significant. RESULTS: Two hundred and ninety-one youngsters were screened by calibrated dentists. The majority (59%) of participants were male; age distribution ranged from 8 to 15 years (mean 11.46 ± 2.11). The results of the UPAT demonstrated the existence of functional TMJ pain in 15.46% (n=45) of the patients without significant prevalence (P > 0.05) in this survey group. CONCLUSION: According to the results of the present study, the UPAT demonstrated that it could be an additional tool to detect the existence of functional jaw pain possibly associated with TMD and also a valid instrument to score pain intensity associated with TMD in youngster patients.
Asunto(s)
Trastornos de la Articulación Temporomandibular , Dolor Facial , Humanos , Masculino , Movimiento , Dimensión del Dolor , Encuestas y CuestionariosRESUMEN
The triboelectric effect, charge transfer during sliding, is well established but the thermodynamic driver is not well understood. We hypothesize here that flexoelectric potential differences induced by inhomogeneous strains at nanoscale asperities drive tribocharge separation. Modeling single asperity elastic contacts suggests that nanoscale flexoelectric potential differences of ±1-10 V or larger arise during indentation and pull-off. This hypothesis agrees with several experimental observations, including bipolar charging during stick slip, inhomogeneous tribocharge patterns, charging between similar materials, and surface charge density measurements.
RESUMEN
Purpose: To develop a phantom with optical and thermal properties matched to human prostate. This phantom will provide a platform for the development and characterization of 980 nm laser interstitial thermal therapy (LITT) systems. Methods: A polyacrylamide gel was doped with Naphthol Green B, Intralipid, and Bovine Serum Albumin (BSA). The necessary concentration of each ingredient was determined by measuring the optical properties via fluence measurements and light diffusion theory. LITT was then performed under the same conditions as a previous clinical trial in which temperature was monitored via a thermal probe. The thermal data and induced coagulation zone were compared to clinical data to illustrate the similarity between the phantom and patient. LITT was also performed under magnetic resonance thermometry (MRT). Results: The requisite concentrations of Naphthol Green B, Intralipid and BSA were found to be 0.144% (w/v), 8.06% (v/v) and 31.4% (v/v) respectively. In the native state, the absorption coefficient and reduced scattering coefficient ( µs' ) were found to be 0.66 ± 0.06 cm-1 and 8.27 ± 0.50 cm-1 respectively, with µs' increasing to 17.63 ± 1.41 cm-1 after coagulation. The thermal response of the phantom was similar to that observed clinically with maximum thermal probe measurements of 64.2 °C and 66.9 °C respectively. The shape of the induced coagulation zone was qualitatively and quantitatively similar to the MRT zone of elevated temperature and the coagulation zone observed clinically. Conclusions: A phantom which simulates optical and thermal response to 980 nm LITT was constructed and demonstrated to be similar to human prostate.
Asunto(s)
Hipertermia Inducida/métodos , Fantasmas de Imagen/normas , Próstata/patología , Termometría/métodos , Humanos , MasculinoRESUMEN
BACKGROUND: An oral condition that has largely been ignored in the Down syndrome population is pathological tooth wear. This study is aimed to create more awareness of the reasons underlying the tooth wear observed in patients with Down syndrome and to suggest different methods to prevent this condition. This research also potentially serves as a platform for future researchers to perform an in-depth analysis of the factors we identified. The aim of this study was to determine if children with Down syndrome are more prone to tooth wear than children who do not have Down syndrome. METHODS: Our sample consisted of 120 children with Down syndrome who were compared with 120 children with no disabilities. The parents or guardians were asked to complete a questionnaire and a 3-day diet chart, while the wear on each tooth was recorded using the standardised Simplified Smith and Knight Tooth Wear Index. RESULTS: Children with Down syndrome experience tooth wear more frequently than non-Down syndrome children. A history of asthma, mouth breathing and gastro-oesophageal reflux disease as well as the intake of acidic diet and drinks has exerted significant effects on the prevalence of tooth wear. CONCLUSIONS: The early diagnosis and analysis of the underlying aetiology are important for the management of tooth wear in children with Down syndrome who have shown a greater tendency to develop erosive lesions.
Asunto(s)
Síndrome de Down/epidemiología , Desgaste de los Dientes/epidemiología , Adolescente , Distribución por Edad , Niño , Preescolar , Comorbilidad , Estudios Transversales , Femenino , Humanos , Masculino , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Turquía/epidemiologíaRESUMEN
BACKGROUND: To date, research on the opinions of dentists on the oral health care of children with DS (Down Syndrome) is scarce. MATERIAL AND METHODS: Evaluate the views and knowledge of Belgium dentists regarding dental care of children with DS. An adequate sample of dentists were invited to fill in a validated questionnaire. Results were assessed in 95% confidence interval with p< 0.05 level. RESULTS: A total of 356 questionnaires were returned (177 men, 179 women). Mean age of the dentists was 50.3 years (SD: 11.9) and 75% obtained their degree more than 20 years ago. 72.5% of all dentists replied that they had not been instructed in how to treat children with DS during their dental educational training, whereas this is only the case for 39% of the dentists who obtained their degree less than 10 years ago. Half of the group indicated that additional training and education would be (very) desirable (52.8%). CONCLUSIONS: Dentists don't seem to feel comfortable in treating children with DS and refer them to a special care dentistry centre in a hospital. It is positive that dentists are in favour of obtaining additional training and education to help them feel more confident in treating children with DS in daily practice. However we must not conclude that because students or qualified dentists received such training that they will automatically treat more patients with special needs.
Asunto(s)
Atención Dental para Niños , Síndrome de Down , Actitud del Personal de Salud , Bélgica , Niño , Atención Odontológica , Odontólogos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y CuestionariosRESUMEN
BACKGROUND: Special Olympics (SO) events represent an opportunity to obtain considerable information regarding intellectual disable (ID) patients. Studies done with SO data have shown an overview of the oral health status of these athletes; however, no information exists regarding the erosive tooth wear (ETW). Therefore, the aim of this study is to determine the presence and severity of ETW in athletes with ID who participated in the SO Belgium 2016. METHODS: The study population consisted in 232 athletes with ID who participated in the SO special smiles program, Belgium 2016. For analysis, the sample was divided in three groups: a) athletes with ID under the age of 25 not diagnosed with Down Syndrome (DS) (n = 174), b) athletes with DS under the age of 25 (n = 39) and c) athletes with DS from 25 and older ages (n = 58). Two calibrated dentists performed dental examinations using the Basic Erosive Wear Examination Index (BEWE). The BEWE sum > 0 was used to determine prevalence of ETW. Severity was determined by two- indicators: 1) By risk levels (low, medium and high risk) proposed by the BEWE index, and 2) by the highest score reached per subject in at least one tooth (BEWE1, 2 or 3). Chi-square test and Mann-Whitney U test were used to detect significant differences among different groups (p < 0.05). RESULTS: The prevalence of ETW for young athletes with ID was 51.14%. Within these athletes, the DS group presented a significant higher mean BEWE sum (4.67, SD 5.64) and prevalence of ETW (69.2%BEWE> 0) when compared to athletes without DS (mean BEWE sum: 1.96, SD 3.47 and 46.3% BEWE> 0; p < 0.05). Furthermore, a significantly higher percentage of athletes with DS were considered at high risk of ETW (p < 0.05). CONCLUSIONS: As a conclusion, half of the young athletes with ID presented at least one affected surface with ETW. The recorded prevalence and severity of ETW for the younger group of athletes with DS was distinctly higher than the athletes with ID not having DS. This shows the need to generate knowledge in order to provide correct management and prevention of erosive tooth wear in populations with ID.
Asunto(s)
Discapacidad Intelectual , Erosión de los Dientes , Desgaste de los Dientes/epidemiología , Anciano , Atletas , Bélgica , Humanos , Persona de Mediana Edad , PrevalenciaRESUMEN
PURPOSE: To define the role of focal laser ablation (FLA) as clinical treatment of prostate cancer (PCa) using the Delphi consensus method. METHODS: A panel of international experts in the field of focal therapy (FT) in PCa conducted a collaborative consensus project using the Delphi method. Experts were invited to online questionnaires focusing on patient selection and treatment of PCa with FLA during four subsequent rounds. After each round, outcomes were displayed, and questionnaires were modified based on the comments provided by panelists. Results were finalized and discussed during face-to-face meetings. RESULTS: Thirty-seven experts agreed to participate, and consensus was achieved on 39/43 topics. Clinically significant PCa (csPCa) was defined as any volume Grade Group 2 [Gleason score (GS) 3+4]. Focal therapy was specified as treatment of all csPCa and can be considered primary treatment as an alternative to radical treatment in carefully selected patients. In patients with intermediate-risk PCa (GS 3+4) as well as patients with MRI-visible and biopsy-confirmed local recurrence, FLA is optimal for targeted ablation of a specific magnetic resonance imaging (MRI)-visible focus. However, FLA should not be applied to candidates for active surveillance and close follow-up is required. Suitability for FLA is based on tumor volume, location to vital structures, GS, MRI-visibility, and biopsy confirmation. CONCLUSION: Focal laser ablation is a promising technique for treatment of clinically localized PCa and should ideally be performed within approved clinical trials. So far, only few studies have reported on FLA and further validation with longer follow-up is mandatory before widespread clinical implementation is justified.
Asunto(s)
Terapia por Láser , Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Técnica Delphi , Humanos , Terapia por Láser/normas , Masculino , Guías de Práctica Clínica como Asunto , Prostatectomía/normasRESUMEN
AIM: The present research aims at reviewing the oral health conditions and treatment needs of people with disabilities in Europe. METHODS: A comprehensive literature search was conducted using Medline and Embase with a timeframe from January 2008 until December 2017. Subsequently, a citation tracking was undertaken. Articles in English, French and Dutch were included. RESULTS: Forty-two articles were included. A variety of oral health problems and treatment needs was reported. More untreated carious lesions, less restorations, a higher number of extractions and less prosthetic rehabilitations were seen in people with disabilities compared with other individuals without disabilities. The oral hygiene level and the periodontal conditions were poor. Moreover, a higher risk of dental trauma, orthodontic problems and tooth wear were reported. DISCUSSION: Different determinants contribute to the oral health condition and treatment needs of people with disabilities. These determinants can be inherent in persons with a disability (biological factors), their lifestyle, the environment or the organization of oral health care. A treatment backlog was a common finding in people with disabilities. However, results need to be interpreted with caution because of the variety of people with disabilities included in this literature review. Proposed solutions can be put at the level of daily oral care, through oral health promotion programs and the creation of a supportive environment, but also at the level of dental attendance, facilitating the access to oral health care services and focusing the training of dental students and dentists. CONCLUSION: This comprehensive review clearly shows a dental treatment backlog in people with disabilities. Solutions require efforts from the caregivers and dental professionals.
Asunto(s)
Atención Odontológica , Personas con Discapacidad , Europa (Continente) , Humanos , Salud Bucal , Higiene BucalRESUMEN
OBJECTIVES: The purpose was to evaluate a combined effect of active ingredients contained in new toothpaste in reducing dentine hypersensitivity. METHODS: The tested toothpaste contained active ingredients potassium nitrate (5.00%) and zinc citrate (0.50%). Pain to water stimulus and blowing air was reported on hypersensitive teeth and measured using the VAS (Visual Analogue Scale). The degree of pain to water stimulus was detected after each subject drank a few sips of water which was boiled to the room temperature. Data were collected on each subject's dental history. RESULTS: A significant reduction in dentine hypersensitivity (26-29% after 2 weeks versus 40% after 4 weeks) was detected in the tested group. The controls also showed significant reduction to both stimuli, but at lower rate. A statistically significant difference to blowing air and water stimuli showed the highest impact for the tested group after 4 weeks (P = 0.033, P = 0.006). CONCLUSION: This study supports the efficacy of the tested toothpaste in reducing the phenomenon of dentine hypersensitivity after 4 weeks of usage.
Asunto(s)
Sensibilidad de la Dentina/prevención & control , Pastas de Dientes/uso terapéutico , Adolescente , Adulto , Citratos/análisis , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nitratos/análisis , Compuestos de Potasio/análisis , Pastas de Dientes/química , Escala Visual Analógica , Adulto Joven , Compuestos de Zinc/análisisRESUMEN
Artificial lungs have been used in the clinic for multiple decades to supplement patient pulmonary function. Recently, small-scale microfluidic artificial lungs (µAL) have been demonstrated with large surface area to blood volume ratios, biomimetic blood flow paths, and pressure drops compatible with pumpless operation. Initial small-scale microfluidic devices with blood flow rates in the µl/min to ml/min range have exhibited excellent gas transfer efficiencies; however, current manufacturing techniques may not be suitable for scaling up to human applications. Here, we present a new manufacturing technology for a microfluidic artificial lung in which the structure is assembled via a continuous "rolling" and bonding procedure from a single, patterned layer of polydimethyl siloxane (PDMS). This method is demonstrated in a small-scale four-layer device, but is expected to easily scale to larger area devices. The presented devices have a biomimetic branching blood flow network, 10 µm tall artificial capillaries, and a 66 µm thick gas transfer membrane. Gas transfer efficiency in blood was evaluated over a range of blood flow rates (0.1-1.25 ml/min) for two different sweep gases (pure O2, atmospheric air). The achieved gas transfer data closely follow predicted theoretical values for oxygenation and CO2 removal, while pressure drop is marginally higher than predicted. This work is the first step in developing a scalable method for creating large area microfluidic artificial lungs. Although designed for microfluidic artificial lungs, the presented technique is expected to result in the first manufacturing method capable of simply and easily creating large area microfluidic devices from PDMS.