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This study aimed to examine if feeding lactating mice a calcium-insufficient diet while simultaneously administering alendronate (ALN) could potentially induce osteocytic osteolysis. Lactating mice were fed calcium (Ca)-insufficient diets with or without ALN administration, and then their femurs were examined for TRAP and ALP, and observed by Kossa staining and transmission electron microscopy (TEM). Mice that had been fed a Ca-insufficient diet were then fed a 44Ca-containing diet, and their tibial sections were examined by isotope microscopy. Mice fed a Ca-insufficient diet had a reduced number of TRAP-positive osteoclasts after ALN administration. ALN-treated, lactating mice fed a Ca-insufficient diet had enlarged lacunae in their cortical bones, and TEM imaging demonstrated expanded regions between osteocytes and lacunar walls. In ALN-treated lactating mice fed a Ca-insufficient diet, huge areas of demineralized bone matrix occurred, centered around blood vessels in the cortical bone. Isotope microscopy showed 44Ca in the vicinity of the osteocytic lacunae, and in the broad, previously demineralized region around the blood vessels in the cortical bone of lactating mice fed a 44Ca-sufficient diet. Bone demineralization likely takes place in the periphery of the osteocytic lacunae and in the broad regions around the blood vessels of lactating mice when they are exposed to severely reduced serum Ca through a Ca-insufficient diet coupled with ALN administration. [ABSTRACT FROM AUTHOR]

Recently, the biological functions of endomucin-positive blood vessels and closely associated αSMA-positive cells in long bones have been highlighted. The surrounding tissues of the flat bones, such as nasal bones covered with mucosa and lamina propria, are different from those of the long bones, indicating the different distributions of endomucin-positive blood vessels and αSMA-reactive cells in nasal bones. This study demonstrates the immunolocalization of endomucin-reactive blood vessels and αSMA-positive cells in the nasal conchae of 3- and 7-week-old mice. The nasal conchae of 3-week-old and 7-week-old male C57BL/6J mice were used for immunoreaction of endomucin, CD34, PDGFbb, TRAP, and c-kit. While we identified abundant endomucin-reactive blood vessels in the lamina propria neighboring the bone, not all were positive for endomucin. More CD34-reactive cells and small blood vessels were observed in the nasal conchae of 3-week-old mice than in those of 7-week-old mice. Some αSMA-positive cells in the nasal conchae surrounded the blood vessels, indicating vascular smooth muscle cells, while other αSMA-immunopositive fibroblastic cells were detected throughout the lamina propria. αSMA-positive cells did not co-localize with c-kit-immunoreactivity, thereby indicating that the αSMA-positive cells may be myofibroblasts rather than undifferentiated mesenchymal cells. Unlike long bones, nasal conchae contain endomucin-positive as well as endomucin-negative blood vessels and exhibit numerous αSMA-positive fibroblastic cells throughout the lamina propria neighboring the bone. Apparently, the distribution patterns of endomucin-positive blood vessels and αSMA-positive cells in nasal conchae are different from those in long bones. [ABSTRACT FROM AUTHOR]

The intermittent administration of parathyroid hormone (PTH) has been prescribed to osteoporotic patients due to its bone anabolic effects. In addition to its actions on bone cells, PTH appears to affect bone-specific blood vessels. These blood vessels are derived from bone marrow sinusoids, which express EphB4, a hallmark of veinous vascular endothelial cells. Given the presence of osteo–vascular interactions, it is important to elucidate the effects of PTH on bone cells and blood vessels in murine models. PTH stimulates preosteoblastic proliferation and osteoblastic bone formation. The former appears to be directly affected by PTH, whereas the latter requires osteoclast-mediated coupling. The administration of PTH through high-frequency dosage schemes accelerates bone turnover featuring remodeling-based bone formation, whereas low-frequency schemes cause mainly remodeling-based and partly modeling-based bone formation. Normally, many blood vessels lack alpha smooth muscle actin (αSMA)-immunoreactive vascular muscle cells surrounding basement membranes, indicating them being capillaries. However, PTH administration increases the number of blood vessels surrounded by αSMA-positive cells. These αSMA-positive cells spread out of blood vessels and express alkaline phosphatase and c-kit, suggesting their potential to differentiate into osteogenic and vascular endothelial/perivascular cells. Unlike bone cells, αSMA-positive cells did not appear in the periphery of blood vessels in the kidney and liver, and the thickness of the tunica media did not change regardless of PTH administration. Based on the results of the study and presence of osseous–vascular interactions, PTH appears to influence not only osteoblastic cells, but also blood vessels in bone. [ABSTRACT FROM AUTHOR]

To verify the biological effects of parathyroid hormone (PTH) on the blood vessels in the bone, this study aimed to investigate histological alterations in endomucin-positive blood vessels and perivascular cells in murine femora after intermittent PTH administration. For comparison with blood vessels in the bone, we examined the distribution of endomucin-positive blood vessels and surrounding αSMA-immunoreactive perivascular cells in the liver, kidney, and aorta with or without PTH administration. Six-week-old male C57BL/6J mice received hPTH [1–34] or vehicle for two weeks. All mice were fixed with a paraformaldehyde solution after euthanasia, and the right femora, kidney, liver, and aorta were extracted for immunohistochemical analysis of endomucin, αSMA, ephrinB2, EphB4, and HIF1α. Light microscopic observations of semi-thin sections and transmission electron microscopic (TEM) observations of ultra-thin sections were performed on the left femora. After intermittent PTH administration, αSMA-reactive/ephrinB2-positive stromal cells appeared around endomucin-positive/EphB4-immunoreactive blood vessels in the bone. In addition, intense immunoreactivities of EphB4 and HIF1α were seen in vascular endothelial cells after the PTH treatment. Several stromal cells surrounding PTH-treated blood vessels exhibited well-developed rough endoplasmic reticulum under TEM observations. In contrast to bone tissues, αSMA-positive stromal cells did not increase around the endomucin-positive blood vessels in the kidney, liver, or aorta, even after PTH administration. These findings show that intermittent PTH administration increases αSMA-reactive/ephrinB2-positive perivascular stromal cells in bone tissue but not in the kidney, liver, or aorta, suggesting that PTH preferentially affects blood vessels in the bone. [ABSTRACT FROM AUTHOR]

Abstract Photocrosslinkable magnetic hydrogels are attracting great interest for tissue engineering strategies due to their versatility and multifunctionality, including their remote controllability ex vivo , thus enabling engineering complex tissue interfaces. This study reports the development of a photocrosslinkable magnetic responsive hydrogel made of methacrylated chondroitin sulfate (MA-CS) enriched with platelet lysate (PL) with tunable features, envisioning their application in tendon-to-bone interface. MA-CS coated iron-based magnetic nanoparticles were incorporated to provide magnetic responsiveness to the hydrogel. Osteogenically differentiated adipose-derived stem cells and/or tendon-derived cells were encapsulated within the hydrogel, proliferating and expressing bone- and tendon-related markers. External magnetic field (EMF) application modulated the swelling, degradation and release of PL-derived growth factors, and impacted both cell morphology and the expression and synthesis of tendon- and bone-like matrix with a more evident effect in co-cultures. Overall, the developed magnetic responsive hydrogel represents a potential cell carrier system for interfacial tissue engineering with EMF-controlled properties. Graphical Abstract A versatile magnetic responsive hydrogel of methacrylated chondroitin sulfate (MA-CS) incorporating iron-based superparamagnetic nanoparticles (MA-CS MNPs) and enriched with platelet lysate was successfully developed. The modulation of intrinsic properties like swelling, degradation and release of platelet lysate-origin growth factors were controlled upon the actuation of an external magnetic field (EMF). Tendon-to-bone magnetic responsive hydrogels units were assembled encapsulating tendon derived cells (TDCs), osteogenically differentiated adipose derived stem cells (O-ASCs) and a co-culture of both under EMF stimulation aiming at interfacial approaches. The developed magnetic system represents a potential cell carrier system for interfacial tissue engineering with EMF-controlled properties. Image 2 [ABSTRACT FROM AUTHOR]

Computer-aided design methods combined with computer-aided manufacturing assist in more accurate and fast removal of nonosteolytic intraosseous pathologies, which are often clinically indistinguishable from adjacent healthy bone tissue. Among these pathologies, idiopathic osteosclerosis is an area of focal radiopacity that cannot be attributed to inflammatory, dysplastic, neoplastic, or systemic disorders. We present here the case of a 54-year-old female patient seeking implant-supported rehabilitation with no other complaints. Computed tomography scan suggested a hyperdense intraosseous lesion in the left mandible. The surgical guide, designed with the add-on OrtogOnBlender, was used to design the bone window through which the osteosclerotic area was approached, preserving bone tissue and reducing operative time. The surgical cavity was filled according to the principles of guided bone regeneration. The patient is awaiting osseointegration of the bone substitute to continue with her surgical-prosthetic treatment. [ABSTRACT FROM AUTHOR]

Purpose: The current data suggest that the presence of lower third molars predisposes the patient to a greater risk of mandibular angle fracture. Thus, the present review sought to determine whether an association exists between the presence of a lower third molar and the occurrence of a mandibular angle fracture in adults and to assess the influence of third molar position according to the Pell and Gregory classification.Materials and Methods: The present study was a systematic review and meta-analysis of analytical observational studies. The present review included all reports of the relationship between mandibular angle fractures and lower third molars. No restriction regarding year, language, or publication status was used. The review protocol was registered at the PROSPERO database (registration no. CRD42016047057). Electronic searches unrestricted for publication period and language were performed in the PubMed, Scopus, SciELO, and Latin American and Caribbean Health Sciences databases. Google Scholar and OpenGrey databases were used to search the "gray literature," avoiding selection and publication biases. The entire search was performed by 2 eligibility reviewers. Association and proportion meta-analyses were planned for the studies with sufficient data. The primary predictor variable was the relationship between the presence of a lower third molar and the development of mandibular angle fractures. The secondary outcome variables were the vertical and horizontal positions of the lower third molar, according to the Pell and Gregory classification and their relationship to the susceptibility to developing a mandibular angle fracture.Results: The search strategies resulted in 411 studies, from which 16 were selected for qualitative and quantitative review. The association meta-analysis included all the selected studies and showed that patients with lower third molars are 3.16 times more likely to develop mandibular angle fractures. The proportion meta-analysis included 5 studies and showed that the overall rate of mandibular angle fractures was 51.58% and that positions III and C are more likely to result in fracture, with a rate of 59.84 and 63.67%, respectively.Conclusions: The results of the present study have shown that the presence of impacted third molars increases by 3.16 times the risk of mandibular angle fractures in adults, with the greatest risk present when third molars are classified as IIIC according to Pell and Gregory. The available evidence is not sufficiently robust to determine whether third molar presence or the level of impaction is the main causative factor for the occurrence of mandibular angle fractures. [ABSTRACT FROM AUTHOR]

This study compared the perception of facial pleasantness and the need for intervention, as assessed by orthodontists, oral and maxillofacial (OMF) surgeons, and laypersons, in people of different ethnicities showing varying degrees of simulated laterognathism. Facial photographs were modified to simulate deviations in the lower face of women of African, Asian and Caucasian descent, ascending in two-degree steps from zero to eight degrees of deviation. Three groups of 20 individuals each (OMF surgeons, orthodontists, and laypersons) assessed the images and rated facial pleasantness on a numerical scale ranging from 0 to 10. The results showed that orthodontists and laypersons rated faces differently only after six and eight degrees of facial change. OMF surgeons rated faces statistically differently from laypersons in all degrees of deviation, and differently from orthodontists in faces with zero, two, and four degrees of deviation. Scores for Caucasian and Asian faces differed only at two degrees of deviation. On the other hand, Caucasian and African faces differed at two and four degrees of deviation, while African and Asian faces differed only at eight degrees. The results suggest that, as a group, OMF surgeons were able to detect all degrees of lower face deviation. Moreover, orthodontists and OMF surgeons seemed to agree in terms of need for facial intervention, and saw that need more often than laypersons. In addition, ethnicity also affected the perception of milder facial changes. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to examine the effect of the side of brain lesion on the ipsilesional hand function of stroke survivors.Methods: Twenty-four chronic stroke survivors, equally allocated in 2 groups according to the side of brain lesion (right or left), and 12 sex- and age-matched healthy controls performed the Jebsen-Taylor Hand Function Test (JTHFT), the Nine-Hole Peg Test (9HPT), the maximum power grip strength (PwGSmax) test, and the maximum pinch grip strength (PnGSmax) test. Only the ipsilesional hand of the stroke survivors and both hands (left and right) of the controls were assessed.Results: PwGS max and PnGS max were similar among all tested groups. Performances in JTHFT and 9HPT were affected by the brain injury. Individuals with left brain damage showed better performance in 9HPT than individuals with right brain damage, but performance in JTHFT was similar.Conclusions: Individuals after a brain injury have the capacity to produce maximum strength preserved when using their ipsilesional hand. However, the dexterity of their hands and digits is affected, in particular for stroke individuals with right brain lesion. [ABSTRACT FROM AUTHOR]

Summary Matrix vesicle-mediated mineralization is an orchestrated sequence of ultrastructural and biochemical events that lead to crystal nucleation and growth. The influx of phosphate ions into the matrix vesicle is mediated by several proteins such as TNAP, ENPP1, Pit1, annexin and so forth. The catalytic activity of ENPP1 generates pyrophosphate (PPi) using extracellular ATPs as a substrate, and the resultant PPi prevents crystal overgrowth. However, TNAP hydrolyzes PPi into phosphate ion monomers, which are then transported into the matrix vesicle through Pit1. Accumulation of Ca 2+ and PO 4 3− inside matrix vesicles then induces crystalline nucleation, with calcium phosphate crystals budding off radially, puncturing the matrix vesicle’s membrane and finally growing out of it to form mineralized nodules. [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was the biological application of focused ion beam-scanning electron microscopy (FIB-SEM) to obtain serial sectional images of skeletal tissues that showed the ultrastructure of 1) cartilaginous extracellular fibrils and 2) osteoblastic cytoplasmic processes. Methods Seven-week-old female wild-type mice were fixed with half-Karnovsky solution and then OsO4, and tibiae were extracted for block staining prior to observation under transmission electron microscope (TEM) and FIB-SEM. Results TEM showed the fine fibrillar but somewhat amorphous ultrastructure of the intercolumnar septa in the growth plate cartilage. In contrast, FIB-SEM revealed bundles of stout fibrils at regular intervals paralleling the septa's longitudinal axis, as well as vesicular structures embedded in the cartilaginous matrix of the proliferative zone. In the primary trabeculae, both TEM and FIB-SEM showed several osteoblastic cytoplasmic processes on the osteoid, in greater numbers than those seen in the bone matrix. FIB-SEM revealed the agglomeration of cytoplasmic processes beneath osteoblasts that formed a tubular continuum extending from those cells. Based on these findings, we postulated that osteoblasts not only extend their cytoplasmic processes to the bone matrix, but also stack these cell processes on the osteoid of the primary trabeculae. Conclusion Taken together, these data suggest that FIB-SEM imaging of serial bone sections may facilitate new insights on the ultrastructure of cartilage and bone tissues. [ABSTRACT FROM AUTHOR]

Evaluate the reproducibility and reliability of a Cefbot-AI software in the identification of cephalometric points in lateral cephalometric radiographs. Thirty lateral cephalometric radiographs obtained with Orthophos XG5/Ceph (Dentsply Sirona, Pennsylvania) were selected, and 19 cephalometric points were marked on each radiograph by a control (ECont) and a calibrated (ECal) examiner and by the Cefbot-AI software (RadioMemory, Belo Horizonte, Brazil). Reliability was assessed by a new analysis of the radiographs 15 days after the first record. Statistical significance was set at P <.05. Excellent reliability was observed in the landmarks of all examiners, as well as in those made by Cefbot-AI (mean intraclass correlation coefficient >0.93). As for reproducibility, comparisons between the performance of ECont and ECal revealed some cephalometric points with a statistically significant difference on the x -axis, namely, S (P =.048), Po (P <.001), and ENA (P =.013). ECont and Cefbot revealed only 1 point, Or (P =.010), with a statistically significant difference on the x -axis. No statistically significant differences were found on the y -axis. Excellent reliability and good reproducibility of Cefbot-AI was observed, suggesting that Cefbot is an excellent auxiliary tool for cephalometric analysis but still dependent on professional assessment for clinical use. [ABSTRACT FROM AUTHOR]

A 74-year-old male patient was referred to the oral and maxillofacial surgery service with a diagnosis of pleomorphic adenoma after a previous incisional biopsy under local anesthesia. The patient had complained of a painless nodular lesion on the hard palate, with slow and progressive growth for 1 year. Upon clinical examination, we observed a nodular lesion, sessile, with a firm consistency, 5.0 cm in its largest diameter and localized on the right side of posterolateral region on the hard palate, extending to the soft palate. Cone beam computed tomography showed no evidence of bone involvement or even communication with the maxillary sinus. After routine preoperative examinations, the patient underwent total excision of the lesion under general anesthesia. Histopathologic analysis of the specimen confirmed the preoperative diagnosis. After 8 months of postoperative follow-up, the surgical site was completely repaired with no signs of recurrence. [ABSTRACT FROM AUTHOR]

Abstract: Osteocytes build up functional syncytia, i.e., the osteocytic lacunar–canalicular system (OLCS). The sites of active bone remodeling revealed the irregularly arranged OLCS, while those of slow remodeling featured well arranged OLCS. This implies that the speed of bone deposition during bone remodeling would affect the regularity of OLCS. Recently, osteocytes were shown to regulate phosphorus serum levels and osteoblastic activity through the expression of fibroblast growth factor (FGF) 23 and sclerostin. In our observations, FGF23 and sclerostin synthesis seemed to be associated with the spatial regularity of the OLCS: both proteins were consistently expressed by osteocytes in epiphyses and cortical bones showing regularly arranged OLCS. In contrast, osteoprotegerin-deficient (OPG−/−) mice revealed rapid bone remodeling with irregular OLCS. Sclerostin-immunoreactivity was markedly diminished in OPG−/− bones. However, sclerostin expression seemed to be a function of osteoclastic and osteoblastic activities rather than being influenced by the regularity of OLCS. This review will introduce our recent studies on the regularity of OLCS and the synthesis of osteocyte-derived FGF23 and sclerostin. [Copyright &y& Elsevier]

Management of skeletal deformities in the maxillofacial region has been an important challenge for medicine and dentistry throughout their evolution as health care sciences. Distraction osteogenesis (DO), also referred to as osteodistraction, is a surgical technique that uses the body’s own repairing mechanisms as allies for optimal tissue reconstruction. This method has gained acceptance and joined the conventional techniques for comprehensive treatment of patients with skeletal insufficiencies, and its successful application in the maxillofacial complex has been extensively reported. The primary aim of this article is to summarize the information on DO, thus contributing to its study, development, and application in challenging situations of our clinical practice as oral and maxillofacial surgeons. [Copyright &y& Elsevier]

The abundance of cellular fibronectin (c-Fn) for ischemic stroke patients and the narrow time-window (<4.5 h) for the decision to administer the thrombolytic treatment with recombinant tissue plasminogen activator (rtPA) are challenging for the development of a point-of-care (PoC) diagnostic platform. We report a case of stratification of ischemic stroke patients based on a magnetoresistive biosensor platform that quantifies the c-Fn levels in a small volume of serum, within the clinically relevant time-window. Our PoC platform uses different ratios of biofunctionalized magnetic nanoparticles (MNPs) as immunoassay labels to adjust the sensitivity within the clinically relevant ranges for c-Fn (1-4 μg/mL). After optimizing the detection range, resolution, and sensitivity, our device was able to stratify ischemic stroke patients who developed hemorrhagic transformation, the main side-effect of rtPA, from those (both non-treated and treated with rtPA) who did not. Cellular fibronectin (c-Fn) is a predictive biomarker for evaluating the risk–benefit of the thrombolytic treatment for ischemic stroke. Present in abundance in the serum of stroke patients, c-Fn is used in this work as a model of challenges encountered in developing biosensors for clinical assays. The systematic optimization of the detection range, resolution, and sensitivity of the assay according to the clinical needs is demonstrated in this investigation. The use of magnetic labels and their versatility when coupled with a portable point-of-care magnetoresistive platform allowed patient stratification in less than 2 h. Unlabelled Image [ABSTRACT FROM AUTHOR]

• Only half (48.0%) of the low-risk women experienced spontaneous labour. • One in seven pregnant women of usual risk were subject to induced labour (14.0%). • More than one third of the women were subject to planned caesarean section (38.0%). • The overall caesarean section rate was 50.5% of low-risk women. • Socioeconomic, obstetric and professional factors associated with planned caesarean section do not justify these patterns of use. This study aimed to examine the prevalence of spontaneous labour, induced labour and planned caesarean section in low-risk women; to identify the contribution of each group to the overall caesarean section rate; and to estimate factors associated with caesarean section in low-risk women according to spontaneous labour, induced labour and planned caesarean section. Cross-sectional hospital-based study of postpartum women and newborns, using data from the survey Birth in Brazil, Southern region. In the sample of 2,668 low-risk women, a descriptive analysis was undertaken and a Multinomial Logistic Regression model was applied to verify associations among caesarean section and spontaneous labour, induced labour and planned caesarean section in comparison with vaginal birth. The results showed the prevalence of spontaneous labour (48.0%), induced labour (14.0%) and planned caesarean sections (38.0%); these frequencies contributed to an overall caesarean section rate of 50.5%. Obstetric characteristics like previous vaginal birth or previous caesarean section were differentially associated with caesarean section, independently of the labour. Caesarean section without labour was significantly associated with age ≥ 35 years (ORadj 5.45 95%CI 3.16–9.39), economic class A and B (ORadj 3.10 95%CI 1.92–4.99), pregnancy between 37 and 38 weeks (ORadj 1.65 95%CI 1.22–2.24), same obstetrician in prenatal and childbirth (ORadj 13.83 95%CI 8.85–21.61) and private payment source at birth (ORadj 11.50 95%CI 6.64–19.93). For low-risk women in Southern Brazil, the results identify high planned caesarean section rates, not associated with socioeconomic, obstetric, institutional or prenatal factors that justify these rates. [ABSTRACT FROM AUTHOR]

Over the past five years, magnetoelectronics has emerged as a promising new platform technology for biosensor and biochip development. The techniques are based on the detection of the magnetic fringe field of a magnetically labeled biomolecule interacting with a complementary biomolecule bound to a magnetic-field sensor. Magnetoresistive-based sensors, conventionally used as read heads in hard disk drives, have been used in combination with biologically functionalized magnetic labels to demonstrate the detection of molecular recognition. Real-world bio-applications are now being investigated, enabling tailored device design, based on sensor and label characteristics. This detection platform provides a robust, inexpensive sensing technique with high sensitivity and considerable scope for quantitative signal data, enabling magnetoresistive biochips to meet specific diagnostic needs that are not met by existing technologies. [Copyright &y& Elsevier]

Highlights • Thermal stability of H ex for MnPt and MnIr was studied in AF/FM bilayers and TMR stacks. • A model was developed to describe the H ex and H c behaviors at high temperatures. • A better thermal stability was observed in TMR stacks than bilayers. Abstract Ensuring a reliable reference in magnetoresistive devices requires robust exchange biased antiferromagnetic/ferromagnetic (AF/FM) bilayers with strong resilience to high temperatures. In this work, we studied the thermal stability of MnPt and MnIr by investigating the exchange bias effect in AF/CoFe bilayers and tunneling magnetoresistance (TMR) full stacks. In bilayers, the obtained blocking temperature ( T b ) of 380 °C for MnPt is higher than T b of 340 °C for MnIr, indicating a better thermal stability. Based on Malozemoff's model, we developed a comprehensive model to describe the exchange bias field ( H ex ) behavior at high temperature by considering the T b distribution and temperature dependence of FM magnetization, giving a good agreement with the experimental data. With increasing temperature, a coercivity ( H c ) enhancement peak was observed in MnIr bilayer, which shows a good agreement with T b distribution. This evidences the H c peak is dominated by the thermal activation of AF grains, indicating that the H c peak only appears at T b center , which is lower than overall T b . The structural properties and grain size of AF layers were studied by X-ray diffraction (XRD), where a mean grain size of 10.6 and 12.6 nm were obtained for MnPt and MnIr, respectively. Compared to bilayers, a more stable thermal behavior was observed in full stacks. In conclusions, our study compared the thermal stability of exchange bias coupling using MnPt and MnIr and developed a comprehensive model to study their temperature dependence. This proposed approach can be used for theoretical studies and experimental designs of AF-based materials for spintronic applications, such as magnetoresistive devices and high density memories. [ABSTRACT FROM AUTHOR]

Highlights • We study annealing effect on memory states stability in CoFeB/MgO/CoFeB based perpendicular MTJs. • Our study indicates a ferromagnetic coupling between the storage and reference layers. • Enhance pMTJs stability by playing perpendicular magnetic anisotropy and interlayer coupling. Abstract Perpendicular magnetic tunnel junctions (p-MTJs) attract great interest because of their excellent performance in spin-transfer-torque magnetic random access memories (STT-MRAMs). The annealing process is critical to achieve the required structural and magnetic properties, therefore obtaining high perpendicular tunneling magnetoresistance (p-TMR) and lower switching current. In this work, the CoFeB/MgO/CoFeB-based p-TMR stack was prepared and a high p-TMR value of 155.9% was obtained from CIPT. The p-MTJs were patterned with pillar sizes ranging from 50 nm to 1000 nm and were annealed upon different annealing temperatures (T A) of 300 and 340 °C. The resistance at parallel (R P) and antiparallel (R AP) state in p-MTJs was obtained upon the application of a ±30 mT perpendicular magnetic field, where the angle of magnetization between storage and reference layer at memory state, θ P and θ AP , were derived from the P and AP resistance ratios with and without magnetic field. The condition θ P = θ AP of about 63.5° was found in as-deposited samples, indicating a ferromagnetic interlayer coupling between storage and reference layers, where θ P = 0° and θ AP = 180° at T A = 300 °C and 340 °C demonstrate a stable memory state. The stability of the resistance state was modeled by considering the evolution of effective perpendicular magnetic anisotropy (K eff) and interlayer coupling constant (J), showing a method to evaluate the ratio of K eff / J via the memory state resistance characterization, where the K eff / J of about −1.26 was obtained in our as-deposited samples. Our study assesses the effect of T A on the θ P and θ AP and supplies the method to enhance the stability through the optimization of perpendicular magnetic anisotropy and interlayer coupling, so to better control the performance of p-MTJ-based STT-MRAMs. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of current monitoring in resonant power converters for overcurrent protection. Since the demand for higher power density suppliers is constantly growing, resonant power converters (RPC) have been receiving more and more attention recently, due to its high efficiency and high switching frequency capability. However, to make practical use of this approach there are still crucial issues, such as overcurrent protection of converter components. Therefore, it is required to implement dedicated protection methods based on a quick feedback loop and additional, modern design solutions. To ensure high reliability of any protection method, as well as to implement new solutions in power electronics, novel current monitoring techniques and sensors are needed. Thus, in this study we present high fidelity magnetoresistive current sensors for monitoring MHz signals with extremely low nonlinearity (< 0,015%), hysteresis (close to 0%) and phase shift (close to 0°). The remarkable effectiveness of the proposed sensors was confirmed by monitoring three different, MHz current waveforms, typically occurring in RPCs with different overcurrent protection methods FFT results clearly emphasize superb signal reproduction, which enables the using of the tested sensors in modern high speed, power electronics applications. [ABSTRACT FROM AUTHOR]

Abstract: An advanced model for quasi-linear spin-valve (SV) structures is presented for circuit simulation purposes. The model takes into account electrical and thermal effects in a coupled way in order to allow a coherent representation of the sensor physics for design purposes of electronics applications based on these sensor devices. The model was implemented in Verilog-A and used in a commercial circuit simulator. For testing the model, different SV structures have been specifically fabricated and measured. The characterization included DC measurements as well as steady-state and transient thermal analysis. From the experimental data, the parameters of the model have been extracted. The model reproduces correctly the experimental measurements obtained for devices with diverse sizes in different electrical and thermal operation regimes. [Copyright &y& Elsevier]

In vitro fertilization (IVF) is the most common assisted reproductive technology used to treat infertility. Embryo selection for transfer in IVF cycles relies on the morphological evaluation by embryologists, either by conventional microscopic assessment or more recently by time-lapse imaging systems. Despite the introduction of time-lapse imaging improvements in IVF success rates have failed to materialize, therefore alternative approaches are needed. Recent studies have shown that embryos resulting in successful pregnancy differ in their secretome and metabolism compared to embryos that fail to implant, suggesting that molecular analysis of embryo culture medium could assist in non-invasive single embryo selection. However, this approach has yet to be adopted clinically due to the lack of appropriate highly sensitive screening technologies needed to assess volume-limited samples. Here we report the detection of hCGβ, IL-8 and TNFα from conditioned culture media of single human embryos using electrochemical impedance spectroscopy. The impedimetric immunosensors revealed that morphologically non-viable embryos produce higher levels of IL-8 and TNFα, associated with abnormal cell division and cell death, respectively. More importantly, hCGβ detection was able to discriminate apparently morphologically identical viable embryos. This work brings an objective dimension to embryo selection, which could overcome the major limitations of morphology-based embryo selection for implantation. Future work should include the validation of these biomarkers in a large patient cohort. • Impedimetric immunosensor for the quantitative quality assessment of single human embryos. • Quantification of chorionic gonadotropin, interleukin-8 and tumor necrosis factor alpha in human embryo conditioned media. • SPE EIS immunosensors achieve lower detection limits than commercial enzyme-linked immunosorbent assays. • Blastocysts with the same morphological grading have different molecular profiles. [ABSTRACT FROM AUTHOR]

Microcystins are the most worldwide extended and common toxins produced by cyanobacteria in freshwater. Microcystin-leucine arginine (MC-LR), associated with the most toxic incidents involving microcystins, are within the cyanobacteria (intracellular) until released into the surrounding waters (extracellular) during cell lysis. Therefore, the relationship between intracellular and extracellular cyanotoxins will allow a comprehensive risk of cyanobacteria-containing waters, preventing disease and improving human safety. In this work, we present the development of a novel portable microfluidic sensing platform for the simultaneous detection of free (extracellular) and total MC-LR (intracellular and extracellular). The integrated system contains the sample processing and detection modules capable of performing the chemical lysis, filtration, sample mixing with antibodies, and electrochemical detection of MC-LR based on an indirect strategy. The performance of the immunosensors was evaluated by electrochemical impedance spectroscopy, showing a linear dynamic range between 3.3 × 10−4 and 10−7 g L−1 and a limit of detection of 5.7 × 10−10 g L−1. The results demonstrate the potential of the developed portable biosensor platform and its suitable application for the analysis of MC-LR at regulated levels for drinking water. Finally, the integrated system was able to simultaneously detect the free and total MC-LR on a Microcystis aeruginosa culture. To the best of our knowledge this is the first described system that can differentiate between intracellular and extracellular concentration of MC-LR. This novel electrochemical sensing platform avoids the multiple processing steps typically needed for standard MC-LR analysis in the laboratory and provides an early warning system for MC-LR remote monitoring in water. • A novel portable electrochemical sensing platform with sample processing integrating enzymatic and chemical lysis, cleaning/filtration, and mixing of the sample with the bio-ligand and detection modules was developed. • Simultaneous detection of free (extracellular) and total (intracellular and extracellular) MC-LR was attained. • Intracellular MC-LR was efficiently released by lysis of Microcystis aeruginosa cells using an enzymatic method. • The developed portable platform is suitable for the analysis of MC-LR at regulated levels for drinking water. [ABSTRACT FROM AUTHOR]