Generation of time-independent torque by ultrasonic guided waves.

The excitation of acoustic waves by a unidirectional transducer, integrated in a piezoelectric cylindrical tube or disk, can lead to a time-independent torque. This phenomenon, demonstrated earlier in experiments and analyzed with coupling-of mode theory, is explained in detail, starting on the level of lattice dynamics of a piezoelectric crystal. Expressions are derived for the stationary torque in the form of integrals over the volume or surface of the piezoelectric, involving the electric potential and displacement field associated with the acoustic waves generated by the transducer. Simulations have been carried out with the help of the finite element method for a tube made of PZT for two cases: A pre-defined potential on the surface of the tube and metal electrodes buried in the piezoelectric. The displacement field and electric potential of the high-frequency acoustic waves (between 200 and 300 kHz) were computed and used in the evaluation of the integrals. The attenuation due to various loss channels of the acoustic waves in the system has been analyzed in detail, as this plays a crucial role for the efficiency of torque generation. It is conjectured that time-reversal symmetry, present in the absence of attenuation, prohibits the generation of a static torque at least in the linear limit. A qualitative comparison is made between the simulations and earlier experiments. Discrepancies are attributed to lack of knowledge of the relevant material constants of the piezoelectric and to a simplified modeling of the electrode geometry in the cylindrical tube, which was necessary for reasons of numerical accuracy.

[Injection treatment for cervical and lumbar syndromes : Special infiltration techniques]. / Injektionstherapie bei Zervikal- und Lumbalsyndromen : Spezielle Infiltrationstechniken.

Minimally invasive injection treatment is indicated particularly in cases of treatment-resistant, painful degenerative alterations of the cervical and lumbar spine, intervertebral disc displacement and radicular syndrome. Through the injections and the supplementation with further conservative, e.g., physical therapy and activating measures, the vicious circle of neural irritation and muscle tension and sympathetic nerve reactions can be interrupted.

[Injection treatment for cervical and lumbar syndromes: principles, indications and general performance]. / Injektionstherapie bei Zervikal- und Lumbalsyndromen: Grundlagen, Indikationen und allgemeine Durchführung.

An intensive conservative treatment that exhausts all treatment options should fundamentally be carried out before every surgical intervention in the region of the spinal column. The therapeutic measures are determined by the extent of the cervical or lumbar syndrome. As a rule, in cases of local complaints symptomatic measures with physiotherapy or digital healthcare applications are indicated. In cases of referred cervical and lumbar syndromes targeted injections can be employed. Before targeted injection treatment a detailed orthopedic clarification with respect to the intensity of local, radicular or pseudoradicular complaints must be carried out. When carrying out minimally invasive injection treatment specific prerequisites with respect to spatial, personnel and technical conditions must be fulfilled. The indications and contraindications must be strictly controlled.

Cortico-spinal modularity in the parieto-frontal system: A new perspective on action control.

Classical neurophysiology suggests that the motor cortex (MI) has a unique role in action control. In contrast, this review presents evidence for multiple parieto-frontal spinal command modules that can bypass MI. Five observations support this modular perspective: (i) the statistics of cortical connectivity demonstrate functionally-related clusters of cortical areas, defining functional modules in the premotor, cingulate, and parietal cortices; (ii) different corticospinal pathways originate from the above areas, each with a distinct range of conduction velocities; (iii) the activation time of each module varies depending on task, and different modules can be activated simultaneously; (iv) a modular architecture with direct motor output is faster and less metabolically expensive than an architecture that relies on MI, given the slow connections between MI and other cortical areas; (v) lesions of the areas composing parieto-frontal modules have different effects from lesions of MI. Here we provide examples of six cortico-spinal modules and functions they subserve: module 1) arm reaching, tool use and object construction; module 2) spatial navigation and locomotion; module 3) grasping and observation of hand and mouth actions; module 4) action initiation, motor sequences, time encoding; module 5) conditional motor association and learning, action plan switching and action inhibition; module 6) planning defensive actions. These modules can serve as a library of tools to be recombined when faced with novel tasks, and MI might serve as a recombinatory hub. In conclusion, the availability of locally-stored information and multiple outflow paths supports the physiological plausibility of the proposed modular perspective.

Distribution of inadvertently excised parathyroid glands during thyroid surgery and the link with post-surgical hypoparathyroidism.

OBJECTIVES: To evaluate the incidence of inadvertent parathyroidectomy, identify risk factors, determine the location of inadvertently excised glands, review pathology reporting in inadvertent parathyroidectomy, and explore relationships between inadvertent parathyroidectomy and post-surgical hypoparathyroidism or hypocalcaemia. METHODS: A retrospective cohort study of 899 thyroidectomies between 2015 and 2020 was performed. Histopathology slides of patients who had an inadvertent parathyroidectomy and a random sample of patients without a reported inadvertent parathyroidectomy were reviewed. RESULTS: Inadvertent parathyroidectomy occurred in 18.5 per cent of thyroidectomy patients. Central neck dissection was an independent risk factor (inadvertent parathyroidectomy = 49.4 per cent with central neck dissection, 12.0 per cent without central neck dissection, p < 0.001). Most excised parathyroid glands were extracapsular (53.3 per cent), followed by subcapsular (29.1 per cent) and intrathyroidal (10.9 per cent). Parathyroid tissue was found in 10.2 per cent of specimens where no inadvertent parathyroidectomy was reported. Inadvertent parathyroidectomy was associated with a higher incidence of six-month post-surgical hypoparathyroidism or hypocalcaemia (19.8 per cent who had an inadvertent parathyroidectomy, 7.7 per cent without inadvertent parathyroidectomy). CONCLUSION: Inadvertent parathyroidectomy increases the risk of post-surgical hypoparathyroidism or hypocalcaemia. The proportion of extracapsular glands contributing to inadvertent parathyroidectomy highlights the need for preventative measures.

Elastomeric biodegradable starch/bentonite nanocomposites. Structure-thermo-mechanical correlation and degradation behavior.

We developed layered silicate nanocomposite films based on corn starch (CS) and bentonite nanoclay, plasticized with glycerol. The films were elastomeric with stretchability of ca. 60-90 % and Tg = -75 to -85 °C. The nanocomposites were exfoliated if cbentonite < 2 wt%, and intercalated if cbentonite > 3 wt%. The exfoliated morphology induced thermal stability as shown by TGA. Interestingly, bentonite induced a reduction of Tg while increasing the Young's modulus E and reducing the extensibility. The fracture energy was a decreasing function of cbentonite except at 2.9 wt%, where the nanocomposite exhibited maximum Young's modulus and toughness, as demonstrated by the Ashby-style plot. The nanocomposite films were biodegradable in anaerobic and aerobic conditions, and in anaerobic conditions the intercalated nanocomposite of cbentonite = 2.9 wt% exhibited slower rate of degradation. These results provide insights into the development of bio-degradable elastomeric food packaging and coatings suitable for sub-ambient conditions.

Lung cancer survival and sex-specific patterns in Portugal: A population-based analysis.

INTRODUCTION: In Portugal, lung cancer (LC) is the first cause of cancer-related death and of death and disability combined. This study aims to analyze the overall survival (OS) and relative survival (RS) of patients diagnosed with LC in 2009-2011 by socio-demographic and tumor characteristics, and analyze sex-specific patterns. METHODS: We estimated 5-year OS using the Kaplan-Meier method and 5-year net survival through the RS framework. Cox regression modeling was used to determine the hazard ratio (HR) of death associated with each independent variable. FINDINGS: For the 11,523 cases analyzed, median 5-year OS was 264 days (95% confidence interval [CI]: 254.8-273.2), the cumulative OS was 13.6% and RS was 15.1%. Males had a lower median survival (237 days; 95% CI: 228.2-245.7) compared to females (416 days; 95% CI: 384.4-447.6) (p < 0.0001) and lower 5-year RS proportions (12.1% vs. 24.9%). RS progressively decreased with age (41.7% for age-group <40 to 7.2% for ≥80) and stage (66.6% for stage I to 2.4% for stage IV). As predictors of decreased survival, we identified male gender, increasing age >50, histologic types (squamous cell carcinoma, non-small cell lung cancer not otherwise specified, other unspecified and small cell lung cancer), and increasing stage. Compared to women, the risk of death in men was 37.7% higher (HR = 1.386; 95% CI: 1.295-1.484). CONCLUSIONS: The differences between OS and RS were small, reflecting the high lethality of LC. Male gender and older age are factors related to poor prognosis. Histology also plays a role in survival prognosis and varies with gender, but the factor related to the worst survival is stage. Although the study reflects data from a decade ago, and major changes occurred in diagnosis, staging and treatment, particularly for advanced disease, as LC mortality is strongly correlated with late stage diagnosis, all efforts should be made to secure early diagnosis and improve survival prospects.

Volumetric Brain MRI Study in Fetuses with Intrauterine Growth Restriction Using a Semiautomated Method.

BACKGROUND AND PURPOSE: According to the medical literature, it is known that intrauterine growth restriction is associated with abnormal fetal brain findings. The aim of this study was to assess the volume of fetal brain structures in fetuses with intrauterine growth restriction compared with the control group and to examine the effect of intrauterine growth restriction on birth weight in relation to the effect on the volumes of these structures. MATERIALS AND METHODS: This historical cohort study included 26 fetuses diagnosed with intrauterine growth restriction due to placental insufficiency. The control group included 66 fetuses with MR imaging scans demonstrating normal brain structures. The volumes of the supratentorial brain, left and right hemispheres, and the cerebellum were measured using a semiautomatic method. In addition, the cerebellum and supratentorial brain ratio was calculated. The measurements of each brain structure were then converted to percentiles according to growth curves. RESULTS: The absolute volumes and percentiles of all brain structures examined were smaller in the intrauterine growth restriction group. All examined brain structures showed results that were statistically significant (P < .015). There was no statistically significant difference in the cerebellum/supratentorial brain ratio (P > .39). The difference in brain volume percentiles was statistically smaller than the difference in birth weight and birth weight percentiles (Dolberg growth curves) between the groups. CONCLUSIONS: Intrauterine growth restriction affects the volume of brain structures, as measured by quantitative MR imaging. Compared with healthy controls, the effect on birth weight was more prominent than the effect on brain structures, possibly due to the "brain-preserving" capability.

Multimodal data fusion of cortical-subcortical morphology and functional network connectivity in psychotic spectrum disorder.

Multiple authors have noted overlapping symptoms and alterations across clinical, anatomical, and functional brain features in schizophrenia (SZ), schizoaffective disorder (SZA), and bipolar disorder (BPI). However, regarding brain features, few studies have approached this line of inquiry using analytical techniques optimally designed to extract the shared features across anatomical and functional information in a simultaneous manner. Univariate studies of anatomical or functional alterations across these disorders can be limited and run the risk of omitting small but potentially crucial overlapping or joint neuroanatomical (e.g., structural images) and functional features (e.g., fMRI-based features) which may serve as informative clinical indicators of across multiple diagnostic categories. To address this limitation, we paired an unsupervised multimodal canonical correlation analysis (mCCA) together with joint independent component analysis (jICA) to identify linked spatial gray matter (GM), resting-state functional network connectivity (FNC), and white matter fractional anisotropy (FA) features across these diagnostic categories. We then calculated associations between the identified linked features and trans-diagnostic behavioral measures (MATRICs Consensus Cognitive Battery, MCCB). Component number 4 of the 13 identified displayed a statistically significant relationship with overall MCCB scores across GM, resting-state FNC, and FA. These linked modalities of component 4 consisted primarily of positive correlations within subcortical structures including the caudate and putamen in the GM maps with overall MCCB, sparse negative correlations within subcortical and cortical connection tracts (e.g., corticospinal tract, superior longitudinal fasciculus) in the FA maps with overall MCCB, and negative relationships with MCCB values and loading parameters with FNC matrices displaying increased FNC in subcortical-cortical regions with auditory, somatomotor, and visual regions.

Human bone marrow-derived mesenchymal stem cells rescue neonatal CPAP-induced airway hyperreactivity.

Continuous positive airway pressure (CPAP) is a primary non-invasive mode of respiratory support for preterm infants. However, emerging evidence suggests CPAP could be an underlying contributor to the unintended pathophysiology of wheezing and associated airway hyperreactivity (AHR) in former preterm infants. The therapeutic benefits of mesenchymal stem cells (MSCs) have been demonstrated in a variety of animal models and several clinical trials are currently underway to assess their safety profiles in the setting of prematurity and bronchopulmonary dysplasia (BPD). In the present study, using a mouse model of neonatal CPAP, we investigated whether conditioned medium harvested from cultures of human bone-marrow derived mesenchymal stem cells (hMSC) could rescue the CPAP-induced AHR, based upon previous observations of their anti-AHR properties. Newborn mice (male and female) were fitted with a custom-made mask for delivery of daily CPAP 3 h/day for the first 7 postnatal days. At postnatal day 21 (two weeks after CPAP ended), lungs were removed, precision-cut lung slices were sectioned and incubated for 48 h in vitro in conditioned medium collected from cultures of three different hMSC donors. As expected, CPAP resulted in AHR to methacholine compared to untreated control mice. hMSC conditioned medium from the cultures of all three donors completely reversed AHR. These data reveal potential therapeutic benefits of hMSC therapy, which may be capable of rescuing the long-term adverse effects of neonatal CPAP on human airway function.

A deep-learning method for the denoising of ultra-low dose chest CT in coronary artery calcium score evaluation.

AIM: To evaluate a novel deep-learning denoising method for ultra-low dose CT (ULDCT) in the assessment of coronary artery calcium score (CACS). MATERIALS AND METHODS: Sixty adult patients who underwent two unenhanced chest CT examinations, a normal dose CT (NDCT) and an ULDCT, were enrolled prospectively between September 2017 to December 201. A special training set was created to learn the characteristics of the real noise affecting the ULDCT implementing a fully convolutional neural network with batch normalisation. Subsequently, the 60 ULDCTs of the evaluation set were denoised. Two blinded radiologists assessed the NDCT, ULDCT, and denoised-ULDCT (DULDCT), assigning a CACS and categorised each scan as having a score above or below 100 and presence of calcifications (score 0 versus >0). Statistical analysis was used to evaluate the agreement between the readers and differences in CACSs between each imaging method. RESULTS: After excluding one patient, the cohort included 59 patients (median age 67 years, 58% men). The ULDCT median effective radiation dose (ERD) was 0.172 mSv, which was 2.8% of the NDCT median ERD. Denoising improved the signal-to-noise ratio by 27.7% (p<0.001). Interobserver agreement was almost perfect between readers (intraclass correlation coefficient >0.993). CACSs were lower for ULDCT and DULDCT as compared to the NDCT (p ≤ 0.001). In differentiating between the presence and absence of coronary artery calcifications, DULDCT showed greater accuracy (98-100%) and positive likelihood ratio (14.29->99) compared to ULDCT (92% and 2.78, respectively). CONCLUSION: DULCT significantly reduced the image noise and better identified patients with no coronary artery calcifications than native ULDCT.

Foreign body ingestion and associated factors in pediatric patients at a tertiary care center.

INTRODUCTION AND AIMS: Foreign body (FB) ingestion is a common problem in children under 5 years of age and is one of the main indications for endoscopy. The aim of the present study was to describe the clinical, radiographic, and endoscopic characteristics of patients with FB ingestion, as well as the factors associated with the anatomic location and the type of object ingested. MATERIALS AND METHODS: An analytic cross-sectional study was conducted on all patients with FB ingestion seen at the gastroenterology service from January 2013 to December 2018. The data were analyzed using the SPSS program, obtaining frequencies, percentages, medians, and interquartile ranges. Associations were assessed through the chi-square test. RESULTS: Eighty-five patients (52 males and 33 females) were included, with a median age of 4 years. The most common symptom was vomiting (29.4%). Two radiographic projections were carried out in 72.9% of the cases and the stomach was the site where the FB was most frequently visualized (32.9%). The objects most commonly ingested were coins (36%), with esophageal location (p<0.05), as well as objects with a diameter larger than 2cm (p<0.05). An endoscopic procedure was performed on 76 patients (89.4%) for FB extraction, with findings of erythema (28.9%), erosion (48.6%), ulcer (10.5%) and perforation (1.3%). CONCLUSIONS: Numerous factors should be taken into account in the approach to FB ingestion in pediatric patients, including type and size of the FB, time interval from ingestion to hospital arrival, and patient clinical status and age.

Is the prefrontal cortex organized by supramodal or modality-specific sensory demands during adolescence?

Attention is inherently biased towards the visual modality during most multisensory scenarios in adults, but the developmental trajectory towards visual dominance has not been fully elucidated. More recent evidence in primates and adult humans suggests a modality-specific stratification of the prefrontal cortex. The current study therefore used functional magnetic resonance imaging (fMRI) to investigate the neuronal correlates of proactive (following cues) and reactive (following probes) cognitive control for simultaneous audio-visual stimulation in 67 healthy adolescents (13-18 years old). Behavioral results were only partially supportive of visual dominance in adolescents, with both reduced response times and accuracy during attend-visual relative to attend-auditory trials. Differential activation of medial and lateral prefrontal cortex for processing incongruent relative to congruent stimuli (reactive control) was also only observed during attend-visual trials. There was no evidence of modality-specific prefrontal cortex stratification during the active processing of multisensory stimuli or during separate functional connectivity analyses. Attention-related modulations were also greater within visual relative to auditory cortex, but were less robust than observed in previous adult studies. Collectively, current results suggest a continued transition towards visual dominance in adolescence, as well as limited modality-specific specialization of prefrontal cortex and attentional modulations of unisensory cortex.

Correlation between 2D and 3D Fetal Brain MRI Biometry and Neurodevelopmental Outcomes in Fetuses with Suspected Microcephaly and Macrocephaly.

BACKGROUND AND PURPOSE: Definitions of fetal microcephaly and macrocephaly are debatable. A better understanding of their long-term prognoses would help guide parental education and counseling. This study aimed to explore the correlation between 2D and 3D fetal brain MR imaging biometry results and the long-term neurodevelopmental outcomes. MATERIALS AND METHODS: This analysis is a historical cohort study. Fetal brain biometry was measured on 2D and 3D MR imaging using a volumetric MR imaging semiautomated algorithm. We measured and assessed the following brain structures: the supratentorial brain volume and cerebellar volume and cerebellar volume/supratentorial brain volume ratio, in addition to commonly used 2D brain MR imaging biometric variables, including occipitofrontal diameter, biparietal diameter, and transcerebellar diameter. Microcephaly was defined as ≤ 3rd percentile; and macrocephaly, as ≥ 97th percentile, corresponding to -2 SDs and +2 SDs. The neurodevelopmental outcome of this study cohort was evaluated using the Vineland-II Adaptive Behavior Scales, and the measurements were correlated to the Vineland standard scores. RESULTS: A total of 70 fetuses were included. No significant correlation was observed between the Vineland scores and either the supratentorial brain volume, cerebellar volume, or supratentorial brain volume/cerebellar volume ratio in 3D or 2D MR imaging measurements, after correction for multiple comparisons. No differences were found among fetuses with macrocephaly, normocephaly, or microcephaly regarding the median Vineland standard scores. CONCLUSIONS: Provided there is normal brain structure on MR imaging, the developmental milestone achievements in early years are unrelated to 2D and 3D fetal brain MR imaging biometry, in the range of measurements depicted in this study.

The role of soil in the contribution of food and feed.

Soils play a critical role in the production of food and feed for a growing global population. Here, we review global patterns in soil characteristics, agricultural production and the fate of embedded soil nutrients. Nitrogen- and organic-rich soils supported the highest crop yields, yet the efficiency of nutrient utilization was concentrated in regions with lower crop productivity and lower rates of chemical fertilizer inputs. Globally, soil resources were concentrated in animal feed, resulting in large inefficiencies in nutrient utilization and losses from the food system. Intercontinental transport of soil-derived nutrients displaced millions of tonnes of nitrogen and phosphorus annually, much of which was ultimately concentrated in urban waste streams. Approximately 40% of the global agricultural land area was in small farms providing over 50% of the world's food and feed needs but yield gaps and economic constraints limit the ability to intensify production on these lands. To better use and protect soil resources in the global food system, policies and actions should encourage shifts to more nutrient-efficient diets, strategic intensification and technological improvement, restoration and maintenance of soil fertility and stability, and enhanced resilience in the face of global change. This article is part of the theme issue 'The role of soils in delivering Nature's Contributions to People'.

Esophagogastric junction outflow obstruction in the differential diagnosis of post-fundoplication dysphagia in children.

INTRODUCTION AND AIMS: Post-fundoplication dysphagia is resolved with no therapeutic intervention in the majority of cases but it can persist in 5.3% of children that undergo the procedure. Among the differential diagnoses, esophagogastric junction outflow obstruction (EGJOO) is a disorder that should be suspected if there is a persistence of dysphagia. The aim of our study was to describe the clinical characteristics, treatment, and follow-up in a case series of patients diagnosed with post-fundoplication EGJOO. MATERIALS AND METHODS: The clinical records of patients diagnosed with EGJOO at a tertiary care hospital within the time frame of September 2015 to September 2019 were reviewed, with respect to manometry, etiology, treatment, and clinical course of the disease. RESULTS: Of the 213 high-resolution esophageal manometries performed, 4 patients met the criteria for post-fundoplication EGJOO. The primary symptom was dysphagia, presenting 15 days after the procedure. Esophageal dilations were carried out on all the patients but with no improvement. Symptoms related to the condition resolved spontaneously in three of the four patients. CONCLUSION: The management of children with post-fundoplication EGJOO continues to be a challenge. Even though more than half of the cases resolve with no intervention, optimum management of the motility disorder is still limited, given the scant experience with the condition in the pediatric population.

Foreign body ingestion and associated factors in pediatric patients at a tertiary care center. / Ingesta de cuerpo extraño en pacientes pediátricos en un hospital de tercer nivel y factores asociados.

INTRODUCTION AND AIMS: Foreign body (FB) ingestion is a common problem in children under 5 years of age and is one of the main indications for endoscopy. The aim of the present study was to describe the clinical, radiographic, and endoscopic characteristics of patients with FB ingestion, as well as the factors associated with the anatomic location and the type of object ingested. MATERIALS AND METHODS: An analytic cross-sectional study was conducted on all patients with FB ingestion seen at the gastroenterology service from January 2013 to December 2018. The data were analyzed using the SPSS program, obtaining frequencies, percentages, medians, and interquartile ranges. Associations were assessed through the chi-square test. RESULTS: Eighty-five patients (52 males and 33 females) were included, with a median age of 4 years. The most common symptom was vomiting (29.4%). Two radiographic projections were carried out in 72.9% of the cases and the stomach was the site where the FB was most frequently visualized (32.9%). The objects most commonly ingested were coins (36%), with esophageal location (p <0.05), as well as objects with a diameter larger than 2cm (p <0.05). An endoscopic procedure was performed on 76 patients (89.4%) for FB extraction, with findings of erythema (28.9%), erosion (48.6%), ulcer (10.5%) and perforation (1.3%). CONCLUSIONS: Numerous factors should be taken into account in the approach to FB ingestion in pediatric patients, including type and size of the FB, time interval from ingestion to hospital arrival, and patient clinical status and age.

Mid-infrared interference coatings with excess optical loss below 10 ppm.

We present high-reflectivity substrate-transferred single-crystal GaAs/AlGaAs interference coatings at a center wavelength of 4.54 µm with record-low excess optical loss below 10 parts per million. These high-performance mirrors are realized via a novel microfabrication process that differs significantly from the production of amorphous multilayers generated via physical vapor deposition processes. This new process enables reduced scatter loss due to the low surface and interfacial roughness, while low background doping in epitaxial growth ensures strongly reduced absorption. We report on a suite of optical measurements, including cavity ring-down, transmittance spectroscopy, and direct absorption tests to reveal the optical losses for a set of prototype mirrors. In the course of these measurements, we observe a unique polarization-orientation-dependent loss mechanism which we attribute to elastic anisotropy of these strained epitaxial multilayers. A future increase in layer count and a corresponding reduction of transmittance will enable optical resonators with a finesse in excess of 100 000 in the mid-infrared spectral region, allowing for advances in high resolution spectroscopy, narrow-linewidth laser stabilization, and ultrasensitive measurements of various light-matter interactions.