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This study aimed to assess the fracture resistance of mandibular first molars after preparation with 3 different access cavity designs and 2 rotary systems using finite element analysis. Six 3-dimensionally printed mandibular first molars simulating natural teeth received traditional, conservative, and ultraconservative (truss) access cavity preparations. The root canals in each group were instrumented with either XP-Endo Shaper (FKG Dentaire, La Chaux-de-Fonds, Switzerland) or TruNatomy (Dentsply Sirona, Ballaigues, Switzerland) rotary files. The models were individually digitized, and micro–computed tomographic scans were transferred to Mimics software (Materialise NV, Leuven, Belgium) to create a geometric model of the tooth. The designed model was exported to 3-matic software (Materialise NV), and STL files were transferred to Geomagic Design X (3D Systems, Rock Hill, SC). Point cloud data were used for surfacing and transferred to ANSYS software (Ansys, Canonsburg, PA). A 200-N superficial force was applied vertically to the buccal cusps and central fossa, and the maximum and minimum equivalent von Mises stress values were calculated and reported. The traditional and ultraconservative access cavity designs yielded the highest and the lowest von Mises stress values, respectively. In the ultraconservative cavity design, the stress values in pericervical dentin were lower in canal preparation with TruNatomy compared with XP-Endo Shaper. In the traditional and conservative cavity designs, stress was lower in the first 2 mm from the cementoenamel junction in the XP-Endo Shaper group and in the next 3 mm in the TruNatomy group. Stress was lower in the ultraconservative and conservative cavity designs compared with the traditional design. Also, root canal preparation with TruNatomy yielded lower stress values in general compared with XP-Endo Shaper. [ABSTRACT FROM AUTHOR]

High-strength concrete (HSC) utilizes a significantly larger amount of cement than ordinary concrete. The cement production process and the provision of stone aggregates cause severe environmental effects. Therefore, substituting waste materials not only introduces an eco-friendly composite but also has the potential to enhance specific properties of concrete. This research has investigated a novel eco-friendly high-strength concrete devoid of cement, employing slag activated with calcium oxide (HSC-CAM) as a replacement for cement. Additionally, rubber powder and polyethylene terephthalate (PET) were utilized as substitutes for aggregates to improve the thermal characteristics and energy absorption capacity of the HSC-CAM, with PET powder and rubber replacing fine aggregates at volume percentages of 10, 20, and 30. A Life Cycle Assessment (LCA) analysis was conducted using the Impact 2002+ and ReCipe Midpoint methods to evaluate waste materials' application on environmental parameters. Tests were performed to assess impact resistance, thermal conductivity, thermal performance, and mechanical properties, contributing to the assessment of ductility and thermal insulation of the developed concrete. The LCA analysis demonstrated that the developed concrete yielded a 66 % improvement in human health indicators and a 48 % in ecosystem quality indicators. Furthermore, it exhibited a substantial reduction of 78 % in embodied carbon footprint and a notable decrease of 61 % in resource indicators compared to ordinary high-strength concrete (HSC). The results also indicated that including 30 % rubber and PET powder led to a 28 % increase in impact resistance for HSC-CAM and a significant decrease of 31 % and 26 % in thermal conductivity, respectively. • For the first time, the development of high-strength concrete with calcium oxide-activated materials is discussed. • The mechanical characteristics of the developed concrete including compressive, tensile, and bending strength are evaluated. • In order to assess the energy absorption capacity of the developed concrete, an impact resistance test is carried out. • To examine the thermal properties, thermal conductivity coefficient and thermal performance tests are conducted. • The environmental impacts were evaluated using a comprehensive life cycle assessment (LCA) analysis. [ABSTRACT FROM AUTHOR]

Knee osteoarthritis is the common joint disease and one of the major causes of pain and disability in the world. Regarding the people tendency to traditional medicine the present study was designed to survey the activity of Commiphora mukul (C. mukul) drops on knee osteoarthritis for the first time. The present study was performed as a randomized, double-blind placebo-controlled trial with 70 patients with moderate knee osteoarthritis, which divided into two groups, drug recipients and placebo. Twenty drops were administered to the placebo group and the control group was administered 20 drops of drug twice a day for 2 months. The pain, function and clinical health scores of both groups were measured at the beginning and end of the study with Visual Analogue Scale and knee injury and osteoarthritis outcome score evaluation scales. The intervention and control groups were similar in terms of age, gender, pain score and knee function before the intervention. Pain intensity in right and left legs was decreased and exhibited statistically significant differences before and after the intervention in both the intervention group (P < 0.001) and the control group (P < 0.01). Five indices of discomfort and dryness, pain, activity and daily activities, exercise and recreation and quality of life in the intervention group, improved (P < 0.001) though in control group the difference between indices were not significant except exercise and recreation. The consumption of C. mukul extract for 2 months was effective in relieving the symptoms of the knee osteoarthritis in patients and improve the quality of life. [ABSTRACT FROM AUTHOR]

• Chronic noise exposure dysregulates the neuroendocrine system leading to hyperactivity of the hypothalamic-pituitary-adrenal (HPA)-axis. • Stress hormones adversely affect cell biology and neuronal circuitry leading to impairment in behavior. • Enduring dysregulation of the HPA-axis is the most mechanism associated with the harmful noise effects. • Noise stress shows a causative association with diverse landmarks of Alzheimer's disease (AD) with a hyper-susceptibility in females. • Functional and Neuroimaging studies are suggested to quantify the contribution of noise in predisposing AD in human. This review examines the adverse impacts of different noise exposure paradigms on the neuroendocrine system, hippocampal and neocortical structures, cognitive performances, and the development of Alzheimer's disease (AD)-like neuropathological changes in the brain of laboratory animals. Studies were reviewed in three periods during the lifespan including: adult animals exposed to noise, female rodents exposed to noise during gestation, and offspring exposed to noise during the prenatal period. Findings imply that chronic noise exposure dysregulates the neuroendocrine system leading to hyperactivation of the sympathetic divisions of the autonomic nervous system (i.e., the hypothalamic-pituitary-adrenal (HPA)-axis), and increases stress hormones that affect brain and behaviour. Enduring dysregulation of the HPA-axis was the most discussed mechanism for the harmful effect of noise during the lifespan. Studies also suggest a causative association of noise with diverse indicators of the AD-like neuropathology in rodents and a hypersusceptibility in females. The results indicate the importance of future neuroimaging studies to quantify the potential contribution of noise in predisposing cognitive decline and preclinical signs of dementia in humans. [ABSTRACT FROM AUTHOR]

• The absence of bacteria in the root canal system increases the success rate of endodontics. • Photodynamic therapy provides the potential to reduce bacteria from the root canals. • The irradiation dose was an important parameter in the reduction of intracanal biofilm. Eradication of endodontic biofilms from the infected root canal system is still the main concern in endodontics. In this study, the role of the power density parameter in the efficacy of antimicrobial photodynamic therapy (PDT) with toluidine blue O (TBO) and phycocyanin (PC) activated by a 635 nm diode laser (DL) against Enterococcus faecalis biofilm in the root canal model was investigated. The E. faecalis biofilm in the root canal was treated with TBO and PC with different power densities (636, 954, 1273, and 1592 W/cm2). The untreated biofilm represented the control group. After the treatments, the biofilms were analyzed based on the number of colonies per milliliter. TBO and PC activated with 635 nm DL with a power density of 1592 W/cm2 were more efficient in removing E. faecalis biofilms within the root canals than those with a power density of 636 W/cm2 (p = 0.00). The light power density optimized the bacterial reduction of E. faecalis biofilms in the root canal spaces. These results provide information on the decisive parameters for performing PDT on intracanal biofilms. [ABSTRACT FROM AUTHOR]

Environmental distresses occurring during the sensitive periods of early life may exacerbate the vulnerability to develop physical and mental diseases in old age. Studies have shown the impact of prenatal stress (PS) on the endocrine development and reprogramming of hypothalamic-pituitary-adrenal axis functions in association with cognitive development and susceptibility to neuropsychiatric diseases. Long-term exposure to glucocorticoids can damage the brain and intensify the progression of Alzheimer's disease (AD)-like neuropathological changes, especially in females. There is, however, less information as to the link between PS and the risk of developing AD pathology throughout the lifespan. In the present study, male and female APP NL-G-F/NL-G-F offspring of dams exposed to gestational noise stress were compared with the control offspring in corticosterone alternations, cognitive and motor performances, and the onset age and development of amyloid beta (Aβ) plaques across age. The hyperactivity of the hypothalamic-pituitary-adrenal axis, spatial learning, and Aβ development were sex specific, showing persistent high levels of stress and further memory loss in females than males, especially in PS mice. The Aβ deposition was started earlier, by 2–3 months, and exhibited a heightened progression in PS animals. The PS also created a long-lasting anxiety-like behavior and impairment in cognitive function and motor coordination. Our results suggested PS as a risk to exacerbate AD-like neuropathological changes during the lifespan, with higher susceptibility of females. The findings were discussed in line with the most likely mechanisms for the PS effects, that is, dysregulation of the neuroendocrine system and the placenta by the PS. • Prenatal stress (PS) resulted in a persistent HPA-axis hyperactivity across age. • The PS created an enduring anxiety-like behavior and impairment in cognitive and motor performances. • The PS led to an earlier onset and overproduction of the Aβ plaques. • The PS was sex-specific in HPA-axis activity, learning function, and Aβ burden. • Females displayed higher susceptibility for developing Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Background: There have been a few reports about the effects of chronic stroke on auditory temporal processing abilities and no reports regarding the effects of brain damage lateralization on these abilities. Our study was performed on 2 groups of chronic stroke patients to compare the effects of hemispheric lateralization of brain damage and of age on auditory temporal processing.Methods: Seventy persons with normal hearing, including 25 normal controls, 25 stroke patients with damage to the right brain, and 20 stroke patients with damage to the left brain, without aphasia and with an age range of 31-71 years were studied. A gap-in-noise (GIN) test and a duration pattern test (DPT) were conducted for each participant.Results: Significant differences were found between the 3 groups for GIN threshold, overall GIN percent score, and DPT percent score in both ears (P ≤ .001). For all stroke patients, performance in both GIN and DPT was poorer in the ear contralateral to the damaged hemisphere, which was significant in DPT and in 2 measures of GIN (P ≤ .046). Advanced age had a negative relationship with temporal processing abilities for all 3 groups.Conclusions: In cases of confirmed left- or right-side stroke involving auditory cerebrum damage, poorer auditory temporal processing is associated with the ear contralateral to the damaged cerebral hemisphere. Replication of our results and the use of GIN and DPT tests for the early diagnosis of auditory processing deficits and for monitoring the effects of aural rehabilitation interventions are recommended. [ABSTRACT FROM AUTHOR]

Background and aim Aided thresholds can be used for prediction of success of hearing aids and to choose between hearing aids and cochlear implants. This study aimed to compare characteristics of aided and unaided auditory steady-state responses (ASSRs). Methods A total of 30 moderate to profoundly hearing-impaired subjects participated in this study. The subjects underwent acoustic immittance, behavioral audiometry, and ASSR with the modulation rate of 40 Hz, first without a hearing aid and then with a hearing aid. Sixteen people with normal hearing and 17 people with severe hearing loss were included in biological calibration of the sound field. Results There was a significant difference between unaided behavioral and ASSR thresholds in all test frequencies (mean difference of unaided behavioral ASSR thresholds: 6.19 dB; P = 0.02 at 500 Hz, P < 0.001 at 1000 and 2000 Hz, and P = 0.02 for 4000 Hz). There was also a significant difference between aided behavioral and ASSR thresholds at 1000 and 2000 Hz (P < 0.001) but not at 500 (P = 0.14) and 4000 (P = 0.23) Hz (mean difference of behavioral ASSR thresholds was 4.33 dB). Despite observing any unaided responses, aided thresholds could be recorded in some severe to profoundly hearing-impaired subjects. The number of recordable thresholds was directly related to speech clarity and speech-reading ability. Multi-frequency stimulation elevated the ASSR threshold, especially for the higher frequencies and in the aided condition. Conclusion Functional and ASSR gains show less difference than threshold data. Therefore, comparing gains instead of thresholds is more accurate for validation of hearing aids. The probability of success of hearing aids appears to be poor if ASSRs (especially aided ones) cannot be recorded. If special care is taken in the fitting of hearing aids and the testing conditions, aided ASSR testing could be a useful tool for validation of hearing aids and the cochlear implant decision-making process. This article is part of a Special Issue entitled . [ABSTRACT FROM AUTHOR]

Objective There is little information about processing of nonspeech and speech stimuli at the subcortical level in individuals with attention deficit hyperactivity disorder (ADHD). The auditory brainstem response (ABR) provides information about the function of the auditory brainstem pathways. We aim to investigate the subcortical function in neural encoding of click and speech stimuli in children with ADHD. Methods The subjects include 50 children with ADHD and 34 typically developing (TD) children between the ages of 8 and 12 years. Click ABR (cABR) and speech ABR (sABR) with 40 ms synthetic /da/ syllable stimulus were recorded. Results Latencies of cABR in waves of III and V and duration of V-Vn ( P ⩽ 0.027), and latencies of sABR in waves A, D, E, F and O and duration of V-A ( P ⩽ 0.034) were significantly longer in children with ADHD than in TD children. There were no apparent differences in components the sustained frequency following response (FFR). Conclusions We conclude that children with ADHD have deficits in temporal neural encoding of both nonspeech and speech stimuli. Significance There is a common dysfunction in the processing of click and speech stimuli at the brainstem level in children with suspected ADHD. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Researches have shown that in clinical practice, balance disorders in children with congenital or early acquired severe to profound hearing loss are probable. The purposes of present study were to specify the percentage of vestibular evoked myogenic potential (VEMP) and an acoustically evoked, short latency negative response (ASNR) recordings and the relation between their presence and static balance ability and postural control of children with profound sensorineural hearing loss (SNHL). Methods: Thirty children with profound SNHL, with an average age of 6.93 years, underwent the VEMP and auditory brainstem response (ABR) tests. Both VEMP and ABR were recorded at the threshold level through air-conduction stimulation via an insert receiver. The static balance performance of the hearing-impaired children was tested with six exercises and compared with that of 30 age- and sex-matched normal-hearing children as controls. Results: VEMP was recorded in 53.3% of ears and ASNR in 40.0%. VEMP was revealed in all ears with ASNR, and a significant correlation was shown between their presence (p =0.005) and also between the ASNR wave latency and P1 (p =0.0001) and N1 (p =0.004) wave amplitude of VEMP. There was a significant correlation between the presence of VEMP and ASNR with the performance of the children in two static balance skills, namely standing on one leg with eyes open on a line and the same practice on the balance beam (p ≤0.008). Conclusion: There was a close relation between the presence of VEMP and ASNR. Additionally, when ASNR was present, the recording of VEMP could be expected. Successful performance in the static balance exercises with reduced vestibular and somatosensory inputs increased the possibility of the recording of ASNR and VEMP. [Copyright &y& Elsevier]

Summary: Objectives: The present study sought to determine the average ages of suspicion, diagnosis, and amplification of profound hearing loss and intervention in deaf children and to compare at-risk and not-at-risk children based on the studied ages. Methods: This study was conducted on 86 children under 6 years of age with profound bilateral hearing loss in Newsha Aural Rehabilitation Center in Tehran from July to December 2005. Data were gathered through the completion of a questionnaire by the children''s parents, and the children''s medical and rehabilitative records were utilized in order to determine the kind and degree of hearing loss. Results: The mean ages of suspicion, diagnosis, amplification, and intervention were 12.6±8.9, 15.2±9.3, 20.5±11.1, and 22.3±11.6 months, respectively; there being statistically significant differences between them. 47.7% of the children were in the high-risk group, and statistically there were no significant differences between the at-risk and not-at-risk children in the studied ages. Of all the neonatal diseases investigated, hyperbilirubinemia was the most frequent (40.7%), and there were also four cases of meningitis and six cases of measles. In terms of consanguinity, mating of first cousins was 41.9% and mating of second cousins and farther familial relationships was 14%. After suspecting hearing loss in their children, the parents had visited physicians (57%), audiologists (37.2%), speech therapists (2.3%), or other specialists (3.5%) for the first time. The economic circumstances of the families had a significant bearing on the average ages of suspicion, diagnosis, amplification, and intervention. Conclusions: Despite the remarkable improvement in the average ages of suspicion, diagnosis, amplification, and intervention in comparison with those reported in a previous study carried out in Iran (2002), there is still noticeable difference between these ages and those suggested by the Joint Committee on Infant Hearing. [Copyright &y& Elsevier]

• Aging is associated with a global increase of low-frequency rsEEG power and reduced and slowing of alpha activity. • The enhancement of slow and the reduction of fast oscillations is the most common finding in AD. • Graph analysis implicates less efficient interaction between brain regions and supports the disconnection hypothesis of AD. • rsEEG features can be reliable predictors of aMCI at risk for conversion to AD. • Studies show the application of gamma-band stimulation in ameliorating AD. Aging is associated with alterations in cognitive processing and brain neurophysiology. Whereas the primary symptom of amnestic mild cognitive impairment (aMCI) is memory problems greater than normal for age and education, patients with Alzheimer's disease (AD) show impairments in other cognitive domains in addition to memory dysfunction. Resting-state electroencephalography (rsEEG) studies in physiological aging indicate a global increase in low-frequency oscillations' power and the reduction and slowing of alpha activity. The enhancement of slow and the reduction of fast oscillations, and the disruption of brain functional connectivity, however, are characterized as major rsEEG changes in AD. Recent rodent studies also support human evidence of age- and AD-related changes in resting-state brain oscillations, and the neuroprotective effect of brain stimulation techniques through gamma-band stimulations. Cumulatively, current evidence moves toward optimizing rsEEG features as reliable predictors of people with aMCI at risk for conversion to AD and mapping neural alterations subsequent to brain stimulation therapies. The present paper reviews the latest evidence of changes in rsEEG oscillations in physiological aging, aMCI, and AD, as well as findings of various brain stimulation therapies from both human and non-human studies. [ABSTRACT FROM AUTHOR]

Emotion perception plays a major role in proper communication with people in different social interactions. Nonverbal affect bursts can be used to evaluate vocal emotion perception. The present study was a preliminary step to establishing the psychometric properties of the Persian version of the Montreal Affective Voices (MAV) test, as well as to investigate the effect of Parkinson disease (PD) on vocal emotion perception. The short, emotional sound made by pronouncing the vowel "a" in Persian was recorded by 22 actors and actresses to develop the Persian version of the MAV, the Persian Affective Voices (PAV), for emotions of happiness, sadness, pleasure, pain, anger, disgust, fear, surprise, and neutrality. The results of the recordings of five of the actresses and five of the actors who obtained the highest score were used to generate the test. For convergent validity assessment, the correlation between the PAV and a speech prosody comprehension test was examined using a gender- and age-matched control group. To investigate the effect of the PD on emotion perception, the PAV test was performed on 28 patients with mild PD between ages 50 and 70 years. The PAV showed a high internal consistency (Cronbach's α = 0.80). A significant positive correlation was observed between the PAV and the speech prosody comprehension test. The test-retest reliability also showed the high repeatability of the PAV (intraclass correlation coefficient = 0.815, P ≤ 0.001). A significant difference was observed between the patients with PD and the controls in all subtests. The PAV test is a useful psychometric tool for examining vocal emotion perception that can be used in both behavioral and neuroimaging studies. [ABSTRACT FROM AUTHOR]

The rapid degradation of Mg alloys in biodegradable orthopedic applications is a significant concern to be investigated. In this study, a bilayer composite coating based on alginate/akermanite and plasma electrolytic oxidation (PEO/ALG-AK) on the AZ31 Mg alloy was intended to enhance its corrosion resistance. For this purpose, akermanite nanopowder was synthesized using the sol-gel method and characterized by TEM and XRD. The influence of the PEO/ALG-AK coating layer on the physicochemical properties, electrochemical, and immersion behaviors in simulated body fluid (SBF) was compared to that of uncoated and PEO-coated samples. The AFM images revealed that the bilayer coating exhibited the highest average roughness (R a = 781 ± 49.3 nm) among the other samples. The EIS test was conducted after 2, 72, and 168 h of immersion in SBF. The bilayer coatings on Mg alloy consistently demonstrated the highest corrosion resistance due to the ALG/Ak layer covering the PEO coating pores. The results of the polarization test also confirmed the achieved results. Furthermore, the implementation of the coatings, particularly the PEO/ALG-AK coating, illustrated a significant reduction in the release of Mg2+ ions and hydrogen bubbles, resulting in corrosion resistance improvement. Finally, the ability of samples to induce apatite formation was also assessed. The results displayed that the deposits on the bare Mg alloy, PEO, and PEO/ALG-AK coatings exhibited Ca/P ratios of 0.83, 1.11, and 1.57, respectively, which closely resembled the natural bone in the PEO/ALG-AK sample. Hence, this developed bilayer coating can be a suitable candidate for enhanced corrosion resistance and bioactivity (apatite formation ability) in the field of Mg biodegradable implants. [ABSTRACT FROM AUTHOR]

Abstract: The effect of three concentrations of safranal on histamine (H1) receptors was tested on two groups of tracheal chains incubated with: 1) indomethacin, and 2) indomethacin, propranolol and atropine (n =6). The EC50 (effective concentration of histamine causing 50% of maximum response) obtained in the presence of chlorpheniramine and all concentrations of safranal in both groups were significantly greater than those of saline (p <0.05 to p <0.001). The EC50 obtained in the presence of all concentrations of safranal and maximum response of its two higher concentrations (1.25 and 2.5μg/mL) in group 2 were greater than in group 1 (p <0.05 to p <0.001). [Copyright &y& Elsevier]

The present study aimed to evaluate the impacts of lavender and metformin on polycystic ovary syndrome (PCOS) patients. We performed a randomized, double-blind clinical trial including 68 females aged 18 to 45, fulfilling the Rotterdam criteria for PCOS. The patients were randomized to receive lavender (250 mg twice daily) or metformin (500 mg three times a day) for 90 days. The serum progesterone was measured at baseline and after 90 days, one week before their expected menstruation. Moreover, the length of the menstrual cycle was documented. Our results showed that lavender and metformin treatment notably increased the progesterone levels in PCOS patients (increasing from 0.35 (0.66) and 0.8 (0.69) to 2.5 (6.2) and 2.74 (6.27) ng/mL, respectively, P < 0.001). However, we found no significant differences between the increasing effects of both treatments on progesterone levels. In addition, all patients in the lavender or metformin groups had baseline progesterone levels <3 ng/mL, reaching 14 (45.2%) patients >3 ng/mL. Lavender and metformin remarkably attenuated the menstrual cycle length in PCOS patients (decreasing from 56.0 (20.0) and 60 (12.0) to 42.0 (5.0) and 50.0 (14.0) days, respectively, P < 0.001). Furthermore, the decreasing effects of lavender on the menstrual cycle length were greater than the metformin group; however, it was not statistically significant (P = 0.06). Lavender effectively increased progesterone levels and regulated the menstrual cycles in PCOS patients, similar to metformin. Therefore, lavender may be a promising candidate for the treatment of PCOS. [Display omitted] [ABSTRACT FROM AUTHOR]

• Aphasia is characterized by various impairments in speech, language, and cognitive functions. • Individuals with aphasia (IWA) show impairments in WM. • WM training can improve memory performance with good generalizability to non-trained tasks (near transfer effect). • WM training has positive impacts on language performance in IWA (far transfer effect). • WM training is suggested as part of rehabilitation programs in aphasia. Individuals with aphasia (IWA) show various impairments in speech, language, and cognitive functions. Working memory (WM), a cognitive system that functions to hold and manipulate information in support of complex, goal-directed behaviors, is one of the impaired cognitive domains in aphasia. The present study intended to examine the effects of a WM training program on both memory and language performance in IWA. This quasi-experimental study with an active control group was performed on 25 people with mild or moderate Broca's aphasia aged 29–61 years resulting from left hemisphere damage following ischemic stroke. Participants were assigned into two groups, including a training group (n = 13) and a control group (n = 12). The treatment and control groups received WM training and routine speech therapy, respectively. Two separate lists of WM tests, including one list for both pre-training assessment and training program and a second list for the post-training assessment, were used in this study. The treatment group showed significant improvements in both trained and non-trained WM tasks (near transfer effect) and language performance (far transfer effect) compared to the control group. Given the good generalizability of the WM training program on both WM and language performance, WM training is suggested as part of the rehabilitation program in aphasia. [ABSTRACT FROM AUTHOR]