Wide-Bandwidth Nanocomposite-Sensor Integrated Smart Mask for Tracking Multiphase Respiratory Activities.

Wearing masks has been a recommended protective measure due to the risks of coronavirus disease 2019 (COVID-19) even in its coming endemic phase. Therefore, deploying a "smart mask" to monitor human physiological signals is highly beneficial for personal and public health. This work presents a smart mask integrating an ultrathin nanocomposite sponge structure-based soundwave sensor (≈400 µm), which allows the high sensitivity in a wide-bandwidth dynamic pressure range, i.e., capable of detecting various respiratory sounds of breathing, speaking, and coughing. Thirty-one subjects test the smart mask in recording their respiratory activities. Machine/deep learning methods, i.e., support vector machine and convolutional neural networks, are used to recognize these activities, which show average macro-recalls of ≈95% in both individual and generalized models. With rich high-frequency (≈4000 Hz) information recorded, the two-/tri-phase coughs can be mapped while speaking words can be identified, demonstrating that the smart mask can be applicable as a daily wearable Internet of Things (IoT) device for respiratory disease identification, voice interaction tool, etc. in the future. This work bridges the technological gap between ultra-lightweight but high-frequency response sensor material fabrication, signal transduction and processing, and machining/deep learning to demonstrate a wearable device for potential applications in continual health monitoring in daily life.

One-stage Surgical Management for Lumbar Brucella Spondylitis by Posterior Debridement, Autogenous Bone Graft and Instrumentation: A Case Series of 24 Patients.

STUDY DESIGN: Clinical case series. OBJECTIVE: The aim of this study was to explore the efficacy and safety of one-stage debridement, autogenous bone graft, and instrumentation for lumbar brucella spondylitis (LBS) via a posterior approach. SUMMARY OF BACKGROUND DATA: Reports on LBS are sporadic, and the therapeutic effect and safety of surgical interventions have not been assessed in clinical studies. METHODS: Between January 2012 and January 2014, 24 consecutive patients with symptomatic LBS who underwent a one-stage operation that combined debridement, autogenous bone graft, and instrumentation via a posterior approach were enrolled. Back pain was measured using the visual analog scale (VAS). The neurological status was evaluated with the American Spinal Injury Association (ASIA) scale. Bone healing was evaluated based on postoperative plain x-ray or computed tomography. RESULTS: All cases were followed up for an average of 14.3 + 3.5 months. The VAS scores were significantly improved at every follow-up interval. An improvement of at least one grade level was observed in the ASIA score of each patient. The average time of bone fusion was 6.8 + 1.6 months. Significant improvements of the average segmental Cobb angle was observed from a preoperative value of 18.4° + 4.6° to a last follow-up value of 21.1°â€Š±â€Š3.7°. At the last follow up, the titers of antibodies against the standard tube agglutination test, erythrocyte sedimentation rate, and C-reactive protein were negative for all patients. CONCLUSION: For LBS, systemic antibrucellosis chemotherapy is the cornerstone of treatment. When cauda equine syndrome, radiculopathy, spinal instability, and severe back pain caused by extradural nonabsorbable abscess or progressive collapse are present, surgical intervention is inevitable. One-stage debridement, autogenous bone graft, and instrumentation via a posterior approach could represent an alternative treatment for LBS, and the efficacy and safety of these techniques are satisfactory. LEVEL OF EVIDENCE: 4.

Selective enrichment and analysis of acidic peptides and proteins using polymeric reverse micelles and MALDI-MS.

The typical difficulties associated with the detection of acidic peptides (i.e., those with low isoelectric points (pI)) by matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) represent a challenge in some proteomic analyses. Here, reverse micelle-forming amphiphilic homopolymers with positively charged interiors are synthesized and used to selectively enrich low pI peptides from complex mixtures for MALDI-MS detection. When using these polymers, acidic proteolytic peptides that are undetectable during normal MALDI-MS analysis are selectively detected. We show that enrichment of these low pI peptides allows acidic proteins to be selectively targeted for detection in multiprotein digests. In addition, the presence of the positively charged polymers during MALDI-MS analyses enhances peptide ion signals by almost an order of magnitude, thereby achieving reproducible ion signals for acidic peptides at concentrations as low as 100 fM. Concurrent detection of acidic and basic peptides was also facilitated by utilizing a sequential extraction process involving reverse micelle forming polymers with positively and negatively charged interiors.

Enhancement of anhydrous proton transport by supramolecular nanochannels in comb polymers.

Transporting protons is essential in several biological processes as well as in renewable energy devices, such as fuel cells. Although biological systems exhibit precise supramolecular organization of chemical functionalities on the nanoscale to effect highly efficient proton conduction, to achieve similar organization in artificial systems remains a daunting challenge. Here, we are concerned with transporting protons on a micron scale under anhydrous conditions, that is proton transfer unassisted by any solvent, especially water. We report that proton-conducting systems derived from facially amphiphilic polymers that exhibit organized supramolecular assemblies show a dramatic enhancement in anhydrous conductivity relative to analogous materials that lack the capacity for self-organization. We describe the design, synthesis and characterization of these macromolecules, and suggest that nanoscale organization of proton-conducting functionalities is a key consideration in obtaining efficient anhydrous proton transport.

Matrix-assisted laser desorption ionization-mass spectrometry signal enhancement of peptides after selective extraction with polymeric reverse micelles.

Extraction of peptides by reverse micelle-forming amphiphilic homopolymers and subsequent matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) detection of these peptides in the presence of these polymers can significantly enhance peptide ion signals. Here, the mechanism of this MALDI signal enhancement is investigated. We find that the signal enhancement is caused by coalescence of polymer-peptide conjugates into "hotspots" on the MALDI target. Hotspot formation is observed only on hydrophilic surfaces and not hydrophobic surfaces. With the use of an Anchorchip MALDI target, which contains very small hydrophilic spots surrounded by a larger hydrophobic area, we find that this hotspot formation can be further exploited for ultrasensitive MALDI-MS analyses of peptides and peptide mixtures. MALDI-MS signals can be enhanced by 3-5 orders of magnitude when peptides are extracted by the amphiphilic homopolymers and detected on the Anchorchip MALDI target. This signal enhancement combined with the extraction selectivity of these reverse micelle-forming homopolymers makes these materials promising tools for sensitive detection of peptides in complex mixtures.

Amphiphilicity in homopolymer surfaces reduces nonspecific protein adsorption.

Amphiphilic homopolymer films have been immobilized onto substrates to study the interactions of these polymers with proteins. X-ray photoelectron spectroscopy (XPS) was utilized to measure the amount of protein adsorption. Amphiphilic homopolymers have been shown to reduce protein adsorption, despite the high affinity of the hydrophobic or hydrophilic functional groups by themselves toward proteins. This protein-resistant property seems to arise from the unique molecular-scale alternation of incompatible functionalities. The combination of incompatible functionalities with a predefined alternating pattern within a monomer could provide a potential design for nonfouling materials.

Self-assembly of facially amphiphilic dendrimers on surfaces.

Facially amphiphilic dendrimers have been shown to provide significant difference in surface behavior due to subtle changes in structure. The monodendrons are capable of providing hydrophobic surfaces, while the didendrons provide superhydrophobic surfaces. This provides an example of how a molecular level change could result in significant changes in surface behavior. This difference is attributed to the conformational differences exhibited by these dendrimers on surfaces.