ZIF-8-Based Surface Plasmon Resonance and Fabry-Pérot Sensors for Volatile Organic Compounds.

This work explores the use of ZIF-8, a metal-organic framework (MOF) material, for its use in the optical detection of volatile organic compounds (VOCs) in Fabry-Pérot and surface plasmon resonance (SPR)-based sensors. The experiments have been carried out with ethanol (EtOH) and show response times as low as 30 s under VOC-saturated atmospheres, and the estimated limit of detection is below 4000 ppm for both sensor types. The selectivity towards other VOCs is relatively poor, although the dynamics of adsorption/desorption differ for each VOC and could be used for selectivity purposes. Furthermore, the hydrophobicity of ZIF-8 has been confirmed and the fabricated sensors are insensitive to this compound, which is a very attractive result for its practical use in gas sensing devices.

Critical review and recent advances of 2D materials-Based gas sensors for food spoilage detection.

Many people around the world are concerned about meat safety and quality, which has resulted in the ongoing advancement of packaged food technology. Since the emergence of graphene in 2004, the number of studies on layered two-dimensional materials (2DMs) for applications ranging from food packaging to meat quality monitoring has been expanding quickly. Recently, scientists have been working hard to develop a novel class of 2DMs that keep the good things about graphene but don't have zero bandgaps at room temperature. Much work has been done on layered transition metal dichalcogenides (TMDCs) like different metal sulfides and selenides for meat spoilage gas sensors. This review looks at (i) the main indicators of meat spoilage and (ii) the detection methods that can be used to find out if meat has been spoiled, such as chemiresistive, electrochemical, and optical methods. (iii) the role of 2DMs in meat spoilage detection and (iv) the emergence of advanced methods for selective classification of target analytes in meat/food spoilage detection in recent years. Thus, this review demonstrates the potential scope of 2DMs for developing intelligent sensor systems for food and meat spoilage detection with high viability, simplicity, cost-effectiveness, and other multipurpose tools.

Knee Injuries in the Elite American Football Player: A Descriptive Pictorial Imaging and Mechanism of Injury Review.

ABSTRACT: Musculoskeletal injuries are common in American football, with an incidence ranging from approximately 10 to 35 per 1000 playing hours. Injuries occur more commonly in games than in practice. Although several studies have analyzed specific injury types in football, this review aims to describe the most common knee injuries sustained by American football players and to review the existing literature pertaining to the radiologic findings used in the diagnosis of these injuries.

Highly sensitive and selective acute myocardial infarction detection using aptamer-tethered MoS2 nanoflower and screen-printed electrodes.

Acute myocardial infarction (AMI) is one of the leading causes of death worldwide. Cardiac troponin I (cTn1) is a commonly used biomarker for the diagnosis of AMI. Although there are various detection methods for the rapid detection of cTn1 such as optical, electrochemical, and acoustic techniques, electrochemical aptasensing techniques are commonly used because of their ease of handling, portability, and compactness. In this study, an electrochemical cTn1 biosensor, MoS2 nanoflowers on screen-printed electrodes assisted by aptamer, was synthesized using hydrothermal technique. Field emission scanning electron microscopy revealed distinct 2D nanosheets and jagged flower-like 3D MoS2 nanoflower structure, with X-ray diffraction analysis revealing well-stacked MoS2  layers. Voltammetry aptasensing of cTn1 ranges from 10 fM to 1 nM, with a detection limit at 10 fM and a sensitivity of 0.10 nA µM-1  cm-2 . This is a ∼fivefold improvement in selectivity compared with the other proteins and human serum. This novel aptasensor retained 90% of its biosensing activity after 6 weeks with a 4.3% RSD and is a promising high-performance biosensor for detecting cTn1.

Green Synthesis and Applications of ZnO and TiO2 Nanostructures.

Over the last two decades, oxide nanostructures have been continuously evaluated and used in many technological applications. The advancement of the controlled synthesis approach to design desired morphology is a fundamental key to the discipline of material science and nanotechnology. These nanostructures can be prepared via different physical and chemical methods; however, a green and ecofriendly synthesis approach is a promising way to produce these nanostructures with desired properties with less risk of hazardous chemicals. In this regard, ZnO and TiO2 nanostructures are prominent candidates for various applications. Moreover, they are more efficient, non-toxic, and cost-effective. This review mainly focuses on the recent state-of-the-art advancements in the green synthesis approach for ZnO and TiO2 nanostructures and their applications. The first section summarizes the green synthesis approach to synthesize ZnO and TiO2 nanostructures via different routes such as solvothermal, hydrothermal, co-precipitation, and sol-gel using biological systems that are based on the principles of green chemistry. The second section demonstrates the application of ZnO and TiO2 nanostructures. The review also discusses the problems and future perspectives of green synthesis methods and the related issues posed and overlooked by the scientific community on the green approach to nanostructure oxides.

Determination of p53 biomarker using an electrochemical immunoassay based on layer-by-layer films with NiFe2O4 nanoparticles.

A disposable electrochemical immunosensors is presented suitable to detect cancer biomarker p53 using screen-printed carbon electrodes modified with a layer-by-layer (LbL) matrix of carboxylated NiFe2O4 nanoparticles and polyethyleneimine, onto which anti-p53 antibodies were adsorbed. Under optimized conditions, the immunosensors exhibited high surface coverage and high concentration of immobilized antibodies, which allowed for detection of p53 in a wide dynamic range from 1.0 to 10 × 103 pg mL-1, with a limit of detection of 5.0 fg mL-1 at a working potential of 100 mV vs. Ag/AgCl. The immunosensors also exhibited good selectivity with negligible interference upon incubation in complex matrices containing high concentrations of proteins (i.e., fetal bovine serum and cell lysate). The immunosensor performance is among the best reported in the literature for determination of p53, with the additional advantage of being disposable and operating with low-volume solutions.Graphical abstract Schematic representation of immunosensor fabrication depicting the immobilization of specific antibodies against p53 protein onto the surfaces of disposable printed electrodes modified with films of polyethyleneimine and different concentrations of carboxylated magnetic nanoparticles.

All-Carbon Based Flexible Humidity Sensor.

Flexible humidity sensors play important roles in wearable devices and consuming electronics which provide a convenient way between digital and physical worlds. This work presents an easy fabricated method for flexible humidity sensors all based on carbon material including electrodes and functional layers. The interdigital electrodes are made by direct laser writing on commercial Kapton tapes and the transferring to flexible Polydimethylsiloxane (PDMS) substrates. The humidity sensing material is reduced graphene oxide (rGO) in nanometer thickness by electrospray. The rGO flakes covered the micro-size laser induced graphite (LIG), forming rGO-graphite balls, dramatically increase surface areas to interact with water molecules. The results show high precision sensitivity and fast response time for adsorption (0.9 s) and desorption (4.5 s). This method provides a novel method for fabricating cost-effective flexible humidity sensors.

UV-assisted chemiresistors made with gold-modified ZnO nanorods to detect ozone gas at room temperature.

Two kinds of flexible ozone (O3) sensors were obtained by placing pristine ZnO nanorods and gold-modified ZnO nanorods (NRs) on a bi-axially oriented poly(ethylene terephthalate) substrate. The chemiresistive sensor is operated at typically 1 V at room temperature under the UV-light illumination. The ZnO nanorods were prepared via a hydrothermal route and have a highly crystalline wurtzite structure, with diameters ranging between 70 and 300 nm and a length varying from 1 to 3 µm. The ZnO NRs were then coated with a ca. 10 nm gold layer whose presence was confirmed with microscopy analysis. This sensor is found to be superior to detect ozone at a room temperature. Typical figures of merit include (a) a sensor response of 108 at 30 ppb ozone for gold-modified ZnO NRs, and (b) a linear range that extends from 30 to 570 ppb. The sensor is stable, reproducible and selective for O3 compared to other oxidizing and reducing gases. The enhanced performance induced by the modification of ZnO nanorods with thin layer of gold is attributed to the increased reaction kinetics compared to pristine ZnO NRs. The sensing mechanism is assumed to be based on the formation of a nano-Schottky type barrier junction at the interface between gold and ZnO. Graphical abstract Room temperature, flexible UV-enhanced gold modified ZnO nanorods can detect ppb levels of ozone.

A review on chemiresistive room temperature gas sensors based on metal oxide nanostructures, graphene and 2D transition metal dichalcogenides.

Room-temperature (RT) gas sensing is desirable for battery-powered or self-powered instrumentation that can monitor emissions associated with pollution and industrial processes. This review (with 171 references) discusses recent advances in three types of porous nanostructures that have shown remarkable potential for RT gas sensing. The first group comprises hierarchical oxide nanostructures (mainly oxides of Sn, Ni, Zn, W, In, La, Fe, Co). The second group comprises graphene and its derivatives (graphene, graphene oxides, reduced graphene oxides, and their composites with metal oxides and noble metals). The third group comprises 2D transition metal dichalcogenides (mainly sulfides of Mo, W, Sn, Ni, also in combination with metal oxides). They all have been found to enable RT sensing of gases such as NOx, NH3, H2, SO2, CO, and of vapors such as of acetone, formaldehyde or methanol. Attractive features also include high selectivity and sensitivity, long-term stability and affordable costs. Strengths and limitations of these materials are highlighted, and prospects with respect to the development of new materials to overcome existing limitations are discussed. Graphical Abstract The review summarizes the most significant progresses related to room temperature gas sensing by using hierarchical oxide nanostructures, graphene and its derivatives and 2D transition metal dichalcogenides, highlighting the peculiar gas sensing behavior with enhanced selectivity, sensitivity and long-term stability.

Trends associated with distal biceps tendon repair in the United States, 2007 to 2011.

BACKGROUND: Current studies investigating surgical treatment of distal biceps tendon tears largely consist of small, retrospective case series. The purpose of this study was to investigate the current patient demographics, surgical trends, and postoperative complication rates associated with operative treatment of distal biceps tendon tears using a large database of privately insured, non-Medicare patients. METHODS: Patients who underwent surgical intervention for distal biceps tendon tears from 2007 to 2011 were identified using the PearlDiver database. Demographic and surgical data as well as postoperative complications were reviewed. Statistical analysis was performed using linear regression analysis and χ(2) tests, with statistical significance set at P < .05. RESULTS: A total of 1443 patients underwent surgical treatment for distal biceps tendon tears. Men and patients aged 40 to 59 years accounted for 98% and 72% of the cohort, respectively. Regarding surgical technique, reinsertion to the radial tuberosity was preferred (95%) over tenodesis to the brachialis (5%) (P < .01). In total, revision surgery for tendon rerupture occurred in 5.4% of treated patients. The incidence of revision surgery for rerupture in acute and chronic distal biceps tears was 5.1% and 7.0%, respectively (P = .36). Postoperative infection and peripheral nerve injury rates were 1.1% and 0.6%, respectively. CONCLUSION: Surgeons strongly preferred anatomic reinsertion to the radial tuberosity for treatment, regardless of the chronicity of the injury. Postoperative complication rates were similar to those found in prior studies, although the true rate of rerupture may be higher than previously thought.

Anatomic Factors that May Predispose Female Athletes to Anterior Cruciate Ligament Injury.

Female athletes are 2 to 10 times more likely to injure their anterior cruciate ligaments (ACL) than male athletes. There has been greater recognition of this gender discrepancy because female participation in competitive athletics has increased. Previous investigators have divided risk factors into hormonal, neuromuscular response, and anatomic subgroups. Gender variation within these groups may help explain the higher incidence of ACL injury in women. The purpose of this article is to review research examining female-specific anatomy that may predispose women to ACL injury. Specifically, we discuss how women may have increased tibial and meniscal slopes, narrower femoral notches, and smaller ACL, which may place the ACL at risk from injury. These anatomic factors, combined with other female-specific risk factors, may help physicians and researchers better understand why women appear to be more prone to ACL injury.

A systematic review of the advancement on colorimetric nanobiosensors for SARS-CoV-2 detection.

The current pandemic of the acute severe respiratory syndrome coronavirus 2 (SARS-CoV-2) killed about 6.4 million and infected more than 600 million individuals by august of 2022, and researchers worldwide are searching for fast and selective approaches for this virus detection. Colorimetric biosensors are an excellent alternative because they are sensitive, simple, fast, and low-cost for rapid detection of SARS-CoV-2 compared to standard Enzyme-linked immunosorbent assay (ELISA) and Polymerase Chain Reaction (PCR) techniques. This study systematically searched and reviewed literature data related to colorimetric biosensors in detecting SARS-CoV-2 viruses, recovered from the Scopus (n = 16), Web of Science (n = 19), PubMed (n = 19), and Science Direct (n = 17) databases totalizing n = 71 articles. Data were analyzed for the type of nanomaterial, biorecognition material at the detection limit (LOD), and devices designed for diagnostics. The most applied nanomaterial were gold nanoparticles, in their original form and hybrid in quantum dots and core-shell. In addition, we show high specificity in point-of-care (POC) diagnostic devices as a faster and cheaper alternative for clinical diagnosis. Finally, the highlights of the colorimetric biosensor developed for diagnostic devices applied in swabs, surgical masks, and lateral flow immunoassays were presented.

Enhancing post-harvest quality of sapota using ultraviolet-C irradiation: A study on efficacy and effects.

Ultraviolet-C (UV-C) radiation has been identified as a promising method for enhancing the shelf life of fruits and vegetables by reducing microbial count and boosting their defence mechanisms. In this study, the impact of UV-C radiation on the physical, biochemical, and microbial properties of sapota fruits was investigated by subjecting them to different doses (2.5, 5, 7.5, and 10 kJ m-2; 12 ± 1°C; 85-90% relative humidity) to enhance their shelf life. The results revealed that higher doses of UV-C radiation resulted in significantly lower weight loss and higher firmness compared to untreated samples and samples treated with lower doses. Furthermore, UV-C-treated fruits displayed a delayed increase in total soluble solids, total sugar, and reduced sugar content compared to the untreated fruit during storage. The UV-C-treated fruits also exhibited a delayed decline in ascorbic acid and titratable acidity during storage. The treated fruits exhibited significantly higher phenolic content than the untreated fruits. Additionally, significantly lower decay and microbial count were observed in fruits treated with higher doses than in those treated with lower doses. The samples treated with a dose of 7.5 and 10 kJ m-2 had a shelf life of 25 days compared to 14 days for the control fruits.

Nucleic Acid-Based Nanobiosensor (NAB) Used for Salmonella Detection in Foods: A Systematic Review.

Salmonella bacteria is a foodborne pathogen found mainly in food products causing severe symptoms in the individual, such as diarrhea, fever, and abdominal cramps after consuming the infected food, which can be fatal in some severe cases. Rapid and selective methods to detect Salmonella bacteria can prevent outbreaks when ingesting contaminated food. Nanobiosensors are a highly sensitive, simple, faster, and lower cost method for the rapid detection of Salmonella, an alternative to conventional enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) techniques. This study systematically searched and analyzed literature data related to nucleic acid-based nanobiosensors (NABs) with nanomaterials to detect Salmonella in food, retrieved from three databases, published between 2010 and 2021. We extracted data and critically analyzed the effect of nanomaterial functionalized with aptamer or DNA at the limit of detection (LOD). Among the nanomaterials, gold nanoparticles (AuNPs) were the most used nanomaterial in studies due to their unique optical properties of the metal, followed by magnetic nanoparticles (MNPs) of Fe3O4, copper nanoparticles (CuNPs), and also hybrid nanomaterials multiwalled carbon nanotubes (c-MWCNT/AuNP), QD/UCNP-MB (quantum dotes upconverting nanoparticle of magnetic beads), and cadmium telluride quantum dots (CdTe QDs@MNPs) showed excellent LOD values. The transducers used for detection also varied from electrochemical, fluorescent, surface-enhanced Raman spectroscopy (SERS), RAMAN spectroscopy, and mainly colorimetric due to the possibility of visualizing the detection result with the naked eye. Furthermore, we show the magnetic separation system capable of detecting the target amplification of the genetic material. Finally, we present perspectives, future research, and opportunities to use point-of-care (POC) diagnostic devices as a faster and lower cost approach for detecting Salmonella in food as they prove to be viable for resource-constrained environments such as field-based or economically limited conditions.

Recent Advances in Nanomaterial-Based Biosensors for Pesticide Detection in Foods.

Biosensors are a simple, low-cost, and reliable way to detect pesticides in food matrices to ensure consumer food safety. This systematic review lists which nanomaterials, biorecognition materials, transduction methods, pesticides, and foods have recently been studied with biosensors associated with analytical performance. A systematic search was performed in the Scopus (n = 388), Web of Science (n = 790), and Science Direct (n = 181) databases over the period 2016-2021. After checking the eligibility criteria, 57 articles were considered in this study. The most common use of nanomaterials (NMs) in these selected studies is noble metals in isolation, such as gold and silver, with 8.47% and 6.68%, respectively, followed by carbon-based NMs, with 20.34%, and nanohybrids, with 47.45%, which combine two or more NMs, uniting unique properties of each material involved, especially the noble metals. Regarding the types of transducers, the most used were electrochemical, fluorescent, and colorimetric, representing 71.18%, 13.55%, and 8.47%, respectively. The sensitivity of the biosensor is directly connected to the choice of NM and transducer. All biosensors developed in the selected investigations had a limit of detection (LODs) lower than the Codex Alimentarius maximum residue limit and were efficient in detecting pesticides in food. The pesticides malathion, chlorpyrifos, and paraoxon have received the greatest attention for their effects on various food matrices, primarily fruits, vegetables, and their derivatives. Finally, we discuss studies that used biosensor detection systems devices and those that could detect multi-residues in the field as a low-cost and rapid technique, particularly in areas with limited resources.

Discovery of inhibitors of plasminogen activator inhibitor-1: structure-activity study of 5-nitro-2-phenoxybenzoic acid derivatives.

Two novel series of 5-nitro-2-phenoxybenzoic acid derivatives are designed as potent PAI-1 inhibitors using hybridization and conformational restriction strategy in the tiplaxtinin and piperazine chemo types. The lead compounds 5a, 6c, and 6e exhibited potent PAI-1 inhibitory activity and favorable oral bioavailability in the rodents.

Cyclic testing of tibialis tendon allografts for anterior cruciate ligament reconstruction using suture-post versus spiked washer tibial fixation.

BACKGROUND: The purpose of this study was to directly compare spiked washer and suture-post tibial-sided fixation techniques used for anterior cruciate ligament reconstruction by measuring anterior tibial translation during cyclic tests. METHODS: Fresh-frozen human knees were tested using a robotic system that applied 250 cycles of anterior-posterior tibial force (134 N) at 30° flexion, while recording tibial translation. Ten intact knees were tested to collect baseline data for native specimens. A single knee was selected to test ligament reconstructions using doubled tibialis tendon allografts. All grafts were fixed proximally using an EndoButton™, and the tibial end of the graft was fixed with either a spiked washer or with a suture post placed at two different locations (near and distant) relative to the tibial tunnel. FINDINGS: Mean first cycle translation for intact knees was 4.8 (sd 1.8) mm; means after reconstruction were 2.6 (sd 0.9) mm (spiked washer), 10.1 (sd 1.9) mm (suture post near), and 10.4 (sd 1.5) mm (suture post distant). Corresponding means for translation increase over 250 cycles were 0.3 (sd 0.2) mm, 3.6 (sd 1.3) mm, 7.2 mm (sd 0.9) mm, and 8.0 (sd 1.3) mm. All mean increases (first cycle and cyclic) after ACL reconstruction were significantly greater than those for the intact knees, and all means with a suture post were significantly greater than those with a spiked washer. There were no significant differences between mean translations for near and distant suture post locations. INTERPRETATION: Use of suture post fixation for anterior cruciate ligament reconstruction is questioned since increases in anterior tibial translation could lead to excessive post-operative knee laxity and possibly early clinical failure.

In vitro determination of the passive knee flexion axis: Effects of axis alignment on coupled tibiofemoral motions.

The natural passive flexion axis of human cadaveric knees was determined using a technique that minimized coupled tibiofemoral motions (translations and rotations), and the kinematic effects of mal-positioned flexion axes were determined. The femur was clamped in an apparatus that allowed unconstrained tibial motions as the knee was flexed from 0° to 90°. To establish the natural flexion axis, the femur's position was adjusted such that coupled tibiofemoral motions were minimized. Tests were repeated, first with the femur rotated internally and externally from its original position, and again after positioning the femur to flex the knee about the transepicondylar axis. Compared to the transepicondylar axis, flexion about the natural axis significantly reduced mean tibial translation by 66.4% (p < 0.01) and varus-valgus rotation by 70.1% (p <0.01). Mean varus-valgus rotation increased by 3.4° (factor of 4) when the femur was rotated 3° internally or externally from the optimum position. Differences in condylar location coordinates between the transepicondylar and natural flexion axes most likely indistinguishable clinically. Knee flexion about an axis that minimizes coupled tibiofemoral motions could be important for placement and orientation of a femoral total knee component and for specimen alignment during biomechanical knee testing.

Dew Point Measurement Using a Carbon-Based Capacitive Sensor with Active Temperature Control.

Laser-induced graphene (LIG) has both good electrical conductivity and three-dimensional porous structures. Here, porous graphene interdigital electrodes (IDE) were constructed as a capacitive sensor from commercial polymer films by the laser ablation process and transferred to the polydimethylsiloxane (PDMS) substrate. The graphene oxide (GO) adsorption layer was electrosprayed as a humidity sensing structure, and a Peltier device was used to control the temperature to produce the condensation of water vapors. The dew point was identified by the equilibrium state of the capacitor when the adsorption layer and the surface air reached the saturation equilibrium. The performances of the hydrophilic dew point sensing system under different environmental conditions were investigated. The results show that the precision of the carbon-based dew point sensor of ≤±0.8 °C DP with good stability and repeatability is better than those of other dew point instrument based on electrical sensing parameters at ±1.0 °C DP.