Release Period Research Articles

Power Compensation Strategy and Experiment of Large Seedling Tree Planter Based on Energy Storage Flywheel

The intermittent hole-digging tree-planting machine shows a periodic short-time peak load law in planting operation, and the operation process is “idling” for small loads most of the time, leading to large torque fluctuations in the transmission system, unscientific power matching, and high energy consumption. To solve the above problems, this article proposes to use a series of energy-saving flywheels in the transmission system of the tree planting machine. On the premise of obtaining holes that meet the target young tree planting requirements, the optimal power compensation strategy for the flywheel system of the tree planting machine is studied to reduce torque fluctuations in the power transmission system, use smaller power drive units, and save energy. Firstly, the nonlinear multi-body dynamics simulation model of soil cutting by the hole-digging component is established. The boundary and contact conditions are set to simulate the power consumption of the hole-digging component at three rotating speeds. Based on the simulation results, the flywheel power compensation strategy is discussed, and the torque fluctuation of the flywheel balance system is analyzed. The results showed that the higher the speed, the greater the power consumption. The power value suddenly increased from 17.82 kW (1.28 s) to 27.93 kW (1.43 s) when the speed was 220 r/min. Then, the power value rapidly decreased, and the power consumption presented a short-term peak feature. The transmission system’s maximum input power is determined as 17.82 kW according to the various simulated power consumption characteristics. The part exceeding the power consumption is compensated by the energy storage flywheel. The total compensation energy was 2382.5 J. After the flywheel system was involved, the maximum output power of the tractor power output shaft decreased by 36.2%, and the peak torque decreased from 445.7 N·m to 285.1 N·m. The power consumption obtained from the field test and simulation was similar, but the energy required to overcome peak load was jointly provided by the flywheel and the engine. The actual input power of the power output shaft during the energy release period of the flywheel system was 18.51 kW when the rotating speed of the hole-digging component was 220 r/min, and the relative error with the simulation value was 2.43%. The measured actual speed reduction of the flywheel system was 8.9%. After installing an energy storage flywheel in the transmission system of the tree planting machine, the output power of the power unit can be stabilized. Tree planting machines can be equipped with smaller power units, which can reduce energy consumption and exhaust emissions.

Growth of tandem long-mat rice seedlings using controlled release fertilizers: Mechanical transplantation can be more economical and high yielding

The traditional soil-based rice seedling production methods for mechanical transplanting are resource-intensive, time consuming and laborious. The improvement and optimization of nutrient management in soil-less nursery raising methods like tandem long-mat seedlings (TLMS) are necessary for the resource-efficient cultivation of rice. In the present study, a controlled-release fertilizer (CRF)-polymer-coated compound fertilizer with 3 months release period (PCCF-3M) was applied as seedling fertilizer (SF), and five different dosages of SF (SF-0, SF-10, SF-20, SF-30, and SF-40) were compared with an organic substrate as the control (CK). Among all SF treatments, the best results were obtained with the application of 20 g/tray of SF (SF-20), as the seedling quality and machine transplanting quality were comparable to those of CK. In contrast, the lower dosages (SF-0 and SF-10) resulted in low nitrogen content and reduced shoot growth, while the higher dosages (SF-30 and SF-40) resulted in toxicity (increased malondialdehyde accumulation) and inhibited the root growth. Similarly, SF-20 increased panicle number (5.6–7.0%) and yield (4.3–5.3%) compared with CK, which might be related to the remaining SF entangled in the roots supporting the tiller growth of rice seedlings in the field. Moreover, SF-20 reduced the seedling block weight (53.1%) and cost of seedling production (23.5%) but increased the gross margin, indicating that it was easy to handle and economical. Taken together, our results indicate that SF-20 is a cost-effective way to promote the growth and transplanting efficiency of rice seedlings. To our knowledge, this study is the first to determine the optimum dosage of CRF for the soil-less production of rice seedlings.

The Potential of Nabis americoferus and Orius insidiosus as Biological Control Agents of Lygus lineolaris in Strawberry Fields.

The tarnished plant bug, Lygus lineolaris, is a major strawberry pest. Only marginally effective control methods exist to manage this pest. Various predators attack L. lineolaris, but their potential is overlooked. In this study, we explore the potential of two omnivorous predators of the tarnished plant bug: the damsel bug, Nabis americoferus, and the minute pirate bug, Orius insidiosus. Firstly, the predation rate of these predators was measured in laboratory tests. Secondly, their potential release rates and release periods were determined in the field using strawberry plants. The results show that N. americoferus feeds on all nymphal stages and adults of the tarnished plant bug, while O. insidiosus attacks only smaller nymphs (up to the N2 stage). In the field, all tested densities of N. americoferus (0.25, 0.5, and 0.75 individual/plant) reduced the population of the tarnished plant bug for several weeks compared with the control treatment, but the effect of O. insidiosus alone was marginal. Additionally, for all the release periods tested, Nabis americoferus was efficient in reducing the pest population. These results demonstrate the potential of N. americoferus to control the tarnished plant bug in strawberry fields. We discuss the possible application of these results for establishing an effective and economically viable biological control strategy.

Novel Double Cross-Linked Acrylic Acid/Bagasse Cellulose Porous Hydrogel for Controlled Release of Citral and Bacteriostatic Effects.

In this study, double cross-linked acrylic acid/bagasse cellulose (AA/BC) porous hydrogels were first prepared using cold plasma (CP) technology instead of chemical initiators. The structure and properties of porous hydrogels, as well as the controlled release and bacteriostatic application as functional carriers, were investigated. Results showed that a novel double cross-linked hydrogel had been successfully synthesized by utilizing •OH and H+ produced during plasma discharge. The acrylic acid (AA) monomers were successfully grafted onto the main chains of bagasse cellulose (BC), forming a porous three-dimensional network structure. The AA/BC porous hydrogels showed excellent swelling levels and intelligent responses. The release of citral in hydrogel inclusion compounds embedded with citral was controlled by adjusting the pH, and the slow release period was about 2 days. The inclusion compounds presented strong bacteriostatic effects against Escherichia coli and Staphylococcus aureus, extending the shelf life of fruits for about 4 days. Therefore, it can be concluded that CP technology is considered to be an efficient and environmental-friendly initiation technology for preparing hydrogels. The potential application of hydrogel inclusion compounds in the food field is expanded.

Spatial Distribution and Long-Term Persistence of Wolbachia-Infected Aedes aegypti in the Mentari Court, Malaysia.

Dengue is endemic in Malaysia, and vector control strategies are vital to reduce dengue transmission. The Wolbachia strain wAlbB carried by both sexes of Ae. aegypti was released in Mentari Court, a high-rise residential site, in October 2017 and stopped after 20 weeks. Wolbachia frequencies are still being monitored at multiple traps across this site, providing an opportunity to examine the spatiotemporal distribution of Wolbachia and mosquito density with respect to year, residential block, and floor, using spatial interpolation in ArcGIS, GLMs, and contingency analyses. In just 12 weeks, Wolbachia-infected mosquitoes were established right across the Mentari Court site with an overall infection frequency of >90%. To date, the Wolbachia frequency of Ae. aegypti has remained high in all areas across the site despite releases finishing four years ago. Nevertheless, the Wolbachia invaded more rapidly in some residential blocks than others, and also showed a relatively higher frequency on the eighth floor. The Ae. aegypti index tended to differ somewhat between residential blocks, whilst the Ae. albopictus index was relatively higher at the top and bottom floors of buildings. In Mentari Court, only a short release period was required to infiltrate Wolbachia completely and stably into the natural population. The results inform future releases in comparable sites in a dengue control programme.

POLYMORPHIC STABILITY EVALUATION OF DARUNAVIR AND RITONAVIR IN FIXED DOSE DRUG COMBINATION PRODUCT BY X-RAY DIFFRACTION AND DIFFERENTIAL SCANNING CALORIMETRY TECHNIQUES

Evaluation of polymorphism for active ingredients and its stability during manufacturing and storage is a critical task for pharmaceutical firms. For solubility enhancement of ritonavir, hot melt extrusion process was selected through conversion of commercially available crystalline form to amorphous. XRD method (with normal and slow scan) and DSC method was considered for polymorphic evaluation in tablet formulation comprising darunavir 800 mg and ritonavir 100 mg. Specificity and precision of XRD method was justified by no interference of placebo and 5.6% RSD, respectively. The observed correlation coefficient of 0.9991 and average recovery of 98.7% (range 91.5 to 105.1) depicts linearity and recovery power of developed method. Studied DSC method shows exotherm for ritonavir crystalline form II at 127.4 °C and darunavir ethanolate at 105.7 °C, which were specific and sensitive to assess polymorphic form of available drug substances in ritonavir blend as well as in tablet formulation during release and stability period.

Self-cross-linked starch/chitosan hydrogel as a biocompatible vehicle for controlled release of drug

A facile one-pot approach was adopted to prepare a polysaccharide-based hydrogel of oxidized starch (OS)-chitosan. The synthetic monomer-free, eco-friendly hydrogel was prepared in an aqueous solution and employed for controlled drug release application. The starch was first oxidized under mild conditions to prepare its bialdehydic derivative. Subsequently, the amino group-containing a modified polysaccharide, “chitosan” was introduced on the backbone of OS via a dynamic Schiff-base reaction. The bio-based hydrogel was obtained via a one-pot in-situ reaction, where functionalized starch acts as a macro-cross-linker that contributes structural stability and integrity to the hydrogel. The introduction of chitosan contributes to stimuli-responsive properties and thus pH-sensitive swelling behavior was obtained. The hydrogel showed its potential as a pH-dependent controlled drug release system and a maximum of 29 h sustained release period was observed for ampicillin sodium salt drug. In vitro studies confirmed that the prepared drug-loaded hydrogels showed excellent antibacterial ability. Most importantly, the hydrogel could find potential use in the biomedical field due to its facile reaction conditions, biocompatibility along with controlled releasing ability of the encapsulated drug.

Preparation and Evaluation of Rizatriptan Benzoate Loaded Nanostructured Lipid Carrier Using Diff erent Surfactant/Co-Surfactant Systems

Migraine is the second most common neurological illness, aff ecting around one billion people each year; triptans are commonly used in the treatment; rizatriptan benzoate is a member of the triptan class, it’s available as a tablet dosage form. Unfortunately, it undergoes fi rst-pass eff ect after oral intake. The intranasal route of administration represents a solve to such a problem. Because it has a limited permeability, an eff ort has been made to circumvent this hurdle. Nanotechnology’s innovation has off ered a useful answer to several issues in the pharmaceutical fi eld in which it could improve drug permeability. The aim of the present work involved loading rizatriptan benzoate on a nanostructured lipid carrier as an attempt to resolve adversity affi liated with the intended drug. The high-speed homogenization technique prepares six formulas. The formulations’ particle size, polydispersity index, zeta potential, entrapment effi ciency, loading capacity, and in-vitro drug release were studied. Diff erential scanning calorimetry (DSC), Fourier transforms infrared spectroscopy (FTIR), and powder X-ray diff raction (PXRD) was investigated to exclude drug excipient incompatibility and to evaluate the crystallinity state of rizatriptan benzoate before and after formulation. Successful formulations were obtained with an acceptable nanostructured parameter In-vitro drug release profi le illustrates a biphasic pattern in which an immediate followed by a persistent phase over a 6 hours. release period, with an estimated percent of the medication being released with an anomalous release mechanism. The compatibility and crystallinity investigation revealed that rizatriptan benzoate was compatible with the other excipients used in the research, and the drug molecule was found to be in an amorphous state within the lipid matrix. In conclusion, nanostructured lipid carriers might be a potential delivery approach for improving intranasal administration of rizatriptan benzoate.

Synergy between Membrane Currents Prevents Severe Bradycardia in Mouse Sinoatrial Node Tissue

Bradycardia is initiated by the sinoatrial node (SAN), which is regulated by a coupled-clock system. Due to the clock coupling, reduction in the 'funny' current (If), which affects SAN automaticity, can be compensated, thus preventing severe bradycardia. We hypothesize that this fail-safe system is an inherent feature of SAN pacemaker cells and is driven by synergy between If and other ion channels. This work aimed to characterize the connection between membrane currents and their underlying mechanisms in SAN cells. SAN tissues were isolated from C57BL mice and Ca2+ signaling was measured in pacemaker cells within them. A computational model of SAN cells was used to understand the interactions between cell components. Beat interval (BI) was prolonged by 54 ± 18% (N = 16) and 30 ± 9% (N = 21) in response to If blockade, by ivabradine, or sodium current (INa) blockade, by tetrodotoxin, respectively. Combined drug application had a synergistic effect, manifested by a BI prolonged by 143 ± 25% (N = 18). A prolongation in the local Ca2+ release period, which reports on the level of crosstalk within the coupled-clock system, was measured and correlated with the prolongation in BI. The computational model predicted that INa increases in response to If blockade and that this connection is mediated by changes in T and L-type Ca2+ channels.

Outcomes of the 2021-2022 APDS General Surgery Recruitment Process Recommendations

In recent years, mounting challenges for applicants and programs in resident recruitment have catapulted this topic into a top priority in medical education. These challenges span all aspects of recruitment-from the time an applicant applies until the time of the Match-and have widespread implications on cost, applicant stress, compromise of value alignment, and holistic review, and equity. In 2021-2022, the Association of Program Directors in Surgery (APDS) set forth recommendations to guide processes for General Surgery residency recruitment. This work summarizes the APDS 2021-2022 resident recruitment process recommendations, along with their justification and program end-of-cycle program feedback and compliance. This work also outlines the impact of these data on the subsequent 2022-2023 recommendations. After a comprehensive review of the available literature and data about resident recruitment, the APDS Task Force proposed recommendations to guide 2021-2022 General Surgery resident recruitment. Following cycle completion, programs participating in the categorical General Surgery Match were surveyed for feedback and compliance. About 122 of the 342 programs (35.7%) participating in the 2022 categorical General Surgery Match responded. Based on available data in advance of the cycle, recommendations around firm application and interview numbers could not be made. About 62% of programs participated in the first round interview offer period with 86% of programs limiting offers to the number of slots available; 95% conducted virtual-only interviews. Programs responded they would consider or strongly consider the following components in future cycles: holistic review (90%), transparency around firm requirements (88%), de-emphasis of standardized test scores (54%), participation in the ERAS Supplemental application (58%), single first round interview release period (69%), interview offers limited to the number of available slots (93%), 48-hour minimum interview offer response time (98%), operationalization of applicant expectations (88%), and virtual interviews (80%). There was variability in terms of the feedback regarding the timing of the single first round offer period as well as support for a voluntary, live site visit for applicants following program rank list certification. The majority of programs would consider implementing similar recommendations in 2022-2023. The greatest variability around compliance revolved around single interview release and the format of interviews. Future innovation is contingent upon the ongoing collection of data as well as unification of data sources involved in the recruitment process.

Coating with cationic inulin enhances the drug release profile and in vitro anticancer activity of lecithin-based nano drug delivery systems

Core-shell structured lipidic nanoparticles (LNPs) were developed using lecithin sodium acetate (Lec-OAc) ionic complex as a core unit and quaternized inulin (QIn) as the shell part. Inulin (In) was modified using glycidyl trimethyl ammonium chloride (GTMAC) as a positively charged shell part and used for coating the negatively surface charged Lec-OAc. The critical micelle concentration (CMC) of the core was determined as 1.047 × 10−4 M, which is expected to provide high stability in blood circulation as a drug-carrying compartment. The amounts of curcumin (Cur) and paclitaxel (Ptx) loaded to LNPs (CurPtx-LNPs), and quaternized inulin-coated LNPs (Cur-Ptx-QIn-LNPs) were optimized to obtain mono-dispersed particles with maximum payload. The total amount of 2.0 mg of the drug mixture (1 mg Cur and 1 mg Ptx) was the optimized quantity for QIn-LNPs and CurPtx-QIn-LNPs due to the favorable physicochemical properties determined by dynamic light scattering (DLS) studies. This inference was confirmed by differential scanning calorimeter (DSC), and Fourier-transform infrared (FT-IR). SEM and TEM images clearly revealed the spherical shapes of LNPs and QIn-LNPs, and QIn covered the LNPs completely. The cumulative release measurements of Cur and Ptx from CurPtx-QIn-LNPs, along with the kinetic studies, showed a significant decrease in the release period of drug molecules with the effect of the coating. At the same time, Korsmeyer-Peppas was the best diffusion-controlled release model. Coating of the LNPs with QIn increased the cell-internalization of NPs to the MDA-MB-231 breast cancer cell lines, resulting in a better toxicity profile than the empty LNPs.

Analysis of Water-Lifting Aerator Performance Based on the Volume of Fluid Method

Water quality deterioration is a major problem faced by reservoirs globally, owing to the inflow of pollution from industrial and municipal activities. Water-lifting aeration is an in situ water quality improvement technology that mixes and oxygenates deep water bodies in reservoirs to improve pollution control efficiency and water quality. While previous studies have mainly focused on the mixing process in the reservoir outside the water-lifting aerator (WLA), knowledge of the internal flow remains limited. In this study, a two-phase flow within a WLA system was numerically studied using the volume of fluid (VOF) method to comprehensively analyze the internal two-phase flow characteristics and the influence on the water-lifting and oxygenation performance of the system. The statistical analysis results showed that increasing the aeration chamber volume enhanced the bottom oxygenation performance by 27% because of the prolonged time of the deflector plate outlet outflow. Additionally, increasing the air release rate enhanced the water-lifting performance by 47%, which was induced by the shortened air piston release period. This study demonstrates the internal flow mechanism of the WLA and provides technical support for parameter optimization design, which has significant scientific research and engineering application value.

Transcriptome and proteome analyses reveal the potential mechanism of seed dormancy release in Amomum tsaoko during warm stratification

BackgroundIn Amomum tsaoko breeding, the low germination rate is the major limitation for their large-scale reproduction. We found that warm stratification was an effective treatment to break the seed dormancy of A. tsaoko prior to sowing and could be an important component of improving breeding programs. The mechanism of seed dormancy release during warm stratification remains unclear. Therefore, we studied the differences between transcripts and proteomes at 0, 30, 60, and 90 days of warm stratification, to identify some regulatory genes and functional proteins that may cause seed dormancy release in A. tsaoko and reveal their regulatory mechanism.ResultsRNA-seq was performed for the seed dormancy release process, and the number of differentially expressed genes (DEGs) was 3196 in three dormancy release periods. Using TMT-labelling quantitative proteome analysis, a total of 1414 proteins were defined as differentially expressed proteins (DEPs). Functional enrichment analyses revealed that the DEGs and DEPs were mainly involved in signal transduction pathways (MAPK signaling, hormone) and metabolism processes (cell wall, storage and energy reserves), suggesting that these differentially expressed genes and proteins are somehow involved in response to seed dormancy release process, including MAPK, PYR/PYL, PP2C, GID1, GH3, ARF, AUX/IAA, TPS, SPS, and SS. In addition, transcription factors ARF, bHLH, bZIP, MYB, SBP, and WRKY showed differential expression during the warm stratification stage, which may relate to dormancy release. Noteworthy, XTH, EXP, HSP and ASPG proteins may be involved in a complex network to regulate cell division and differentiation, chilling response and the seed germination status in A. tsaoko seed during warm stratification.ConclusionOur transcriptomic and proteomic analysis highlighted specific genes and proteins that warrant further study in fully grasping the precise molecular mechanisms that control the seed dormancy and germination of A. tsaoko. A hypothetical model of the genetic regulatory network provides a theoretical basis for overcoming the physiological dormancy in A. tsaoko in the future.

RETRACTED ARTICLE: Loan repayment performance and its determinants: evidence from micro and small enterprises operating in Dire-Dawa, Ethiopia

Microfinance Institutions (MFIs) reach a large number of poor people who are not served by formal financial institutions and have been a prime element in the economic growth of countries like Ethiopia. To operate successfully MFIs have to make sure that the loan disbursed has to be repaid to have a sustainable and viable financial operation and contribute their own its share in reducing unemployment and poverty reduction. In light of this, this research study was conducted to investigate the factors affecting loan repayment performance and factors affecting it in Micro and Small Enterprises (MSEs) financed by Microfinance Institutions by taking lender characteristics. Primary data was collected using questionnaires and interviews. A total of 175 Micro and Small Enterprises were selected using purposive sampling. Secondary data was acquired from annual reports and financial statements of Microfinance institutions and other institutions. Descriptive analysis as well as econometric analysis was used to analyze the effect of the literature-driven variables on the loan repayment performance of borrowers. The binary logistic regression result revealed that loan repayment period, grace period, and timeliness of loan release have a statistically significant effect on the loan repayment performances of borrowers. Loan size has a statistically insignificant effect on the loan repayment performance of borrowers.

COVID-19 impact on opioid overdose after jail release in Massachusetts

IntroductionRelease from incarceration is a high-risk period for opioid overdose. Concern about COVID-19 spread in jails led to early releases; it is unknown whether pandemic era releases of persons with opioid use disorder (OUD) contributed to increases in community overdose rates. MethodsObservational data compared overdose rates three months after release among jailed persons with OUD released before (9/1/2019–3/9/2020) and during the pandemic (3/10/2020–8/10/2020) from seven jails in Massachusetts. Data on overdoses come from the Massachusetts Ambulance Trip Record Information System and Registry of Vital Records Death Certificate file. Other information came from jail administrative data. Logistic models regressed overdose on release period, controlling for MOUD received, county of release, race/ethnicity, sex, age, and prior overdose. ResultsPandemic releases with OUD had a higher risk of fatal overdose (adjusted odds ratio [aOR] 3.06; 95% CI, 1.49 to 6.26); 20 persons released with OUD (1.3%) experienced a fatal overdose within three months of release, versus 14 (0.5%) pre-pandemic. MOUD had no detectable relationship with overdose mortality. Pandemic release did not impact non-fatal overdose rates (aOR 0.84; 95% CI 0.60 to 1.18), though in-jail methadone treatment was protective (aOR 0.34; 95% CI 0.18 to 0.67). ConclusionsPersons with OUD released from jail during the pandemic experienced higher overdose mortality compared to pre-pandemic, but the number of deaths was small. They did not experience significantly different rates of non-fatal overdose. Early jail releases during the pandemic were unlikely to explain much, if any, of the observed increase in community overdoses in Massachusetts.

Polymer-modified halloysite nanotubes with high adhesion and UV-shielding properties for chlopyrifos application on cotton leaves

Photodegradation and the low retention rate of pesticides on crop leaves seriously affect their utilization rate. Regarding this problem, we have developed an anti-ultraviolet and high-adhesion pesticide carrier based on halloysite nanotubes (Hal) and was loaded with chlorpyrifos (CPF). By grafting polyethylenimine (PEI) and protocatechuic acid (PCA) onto Hal, PEI-g-Hal (pH) and PCA-g-(PEI-g-Hal) (PPH) were obtained. Load CPF into the cavity of PPH by negative pressure to obtain PPH @ CPF. Its structure and morphology were confirmed by TEM, XPS, FT-IR, zeta potential, TG and XRD, etc. The results indicated that the retention rate of PPH@CPF on cotton leaves was 74.33%, estimated as 1.8 times more efficient than that of PH@CPF. The fluorescence intensity of PPH@FITC was better than that of PH@FITC after 5 times of simulated rain wash. With the decrease in pH, the amino group was protonated gradually, PPH@CPF hydrophilicity was enhanced, and the release rate of PPH@CPF increased gradually. At pH = 5–7 (roughly the same as the pH environment on the leaf surface), PPH@CPF has a faster initial rate and a longer sustained release period than in other pH environments. The photodegradation rate of PPH@CPF was 70% after 24 h, which was much lower than the original CPF. The high adhesion and UV-shielding properties of organic modified Hal played a positive role in reducing the photodegradation and improved the retention rate of pesticides on the crop leaf surface, thus having an extensive significance in crop protection and environmental protection.

Posttraumatic Stress Symptoms in Patients With Cancer During the COVID-19 Pandemic: A One-Year Longitudinal Study.

Patients with cancer may be particularly vulnerable to psychological consequences of the COVID-19 pandemic. We studied the prevalence and evolution of posttraumatic stress symptoms (PTSS) in patients with cancer during the pandemic waves, and we investigated factors associated with high symptoms. COVIPACT is a 1-year longitudinal prospective study of French patients with solid/hematologic malignancies receiving treatment during the first nationwide lockdown. PTSS were measured every 3 months from April 2020 using the Impact of Event Scale-Revised. Patients also completed questionnaires on their quality of life, cognitive complaints, insomnia, and COVID-19 lockdown experience. Longitudinal analyses involved 386 patients with at least one PTSS assessment after baseline (median age, 63 years; 76% female). Among them, 21.5% had moderate/severe PTSS during the first lockdown. The rate of patients reporting PTSS decreased at lockdown release (13.6%), increased again at second lockdown (23.2%), and slightly declined from the second release period (22.7%) to the third lockdown (17.5%). Patients were grouped into 3 trajectories of evolution. Most patients had stable low symptoms throughout the period, 6% had high baseline symptoms slowly decreasing over time, and 17.6% had moderate symptoms worsening during the second lockdown. Female sex, feeling socially isolated, worrying about COVID-19 infection, and using psychotropic drugs were associated with PTSS. PTSS were associated with impaired quality of life, sleep, and cognition. Approximately one-fourth of patients with cancer experienced high and persistent PTSS over the first year of the COVID-19 pandemic and may benefit from psychological support. gov identifier: NCT04366154.

Dual-crosslinked network of polyacrylamide-carboxymethylcellulose hydrogel promotes osteogenic differentiation in vitro

In our previous study, we successfully designed a dual-crosslinked network hydrogel by introducing the monomers acrylamide (AM), carboxymethylcellulose (CMC), zeolitic imidazolate framework-8 (ZIF-8), and alendronate (Aln). With the simultaneous presentation of physical and chemical crosslinks, the fabricated hydrogel with 10 % concentration of Aln@ZIF-8 (PAM-CMC-10%Aln@ZIF-8) exhibited excellent mechanical characteristics, high Aln loading efficiency (63.83 %), and a slow release period (6 d). These results demonstrate that PAM-CMC-10%Aln@ZIF-8 is a potential carrier for delaying Aln. In this study, we mainly focused on the biocompatibility and osteogenic ability of PAM-CMC-10%Aln@ZIF-8 in vitro, which is a continuation of our previous work. First, this study investigated the biocompatibility of dual-crosslinked hydrogels using calcein-AM/Propidium Iodide and cell counting kit-8. The morphology of rat bone mesenchymal stem cells was assessed using FITC-phalloidin/DAPI and vinculin immunostaining. Finally, osteogenic induction ability in vitro was assessed via alkaline phosphatase expression and alizarin red S staining, which was also confirmed using real-time PCR at the gene level and immunofluorescence at the protein level. The results indicated that the introduction of Aln enabled a dual-crosslinked hydrogel with superior biocompatibility and outstanding osteogenic differentiation ability in vitro, providing a solid foundation for subsequent animal experiments in vivo.

Effect of wall friction on oscillation of velocity at the head of the gravity current

Velocity oscillations at the head of the gravity current were investigated in experiments and numerical simulations of a locked-exchange flow. A comparison of the experimental and numerical simulations showed that the depth and volume of the released fluid affected the oscillations in the velocity of the gravity current. At the initial stage, the head moved forward at a constant velocity, and velocity oscillations occurred. The head maximum thickness increased at the same time as the head, which did not have a round, and accumulated buoyant fluid due to the buoyancy effect intrusion force. The period of accumulation and release of the buoyant fluid was almost the same as that observed for the head movement velocity; the head movement velocity was faster when the buoyant fluid accumulated and slower when it was released. At the viscous stage, the forward velocity decreased proportionally to the power of 1/2 of time, since the head was not disturbed from behind. As the mass concentration at the head decreased, the gravity current was slowed by the viscous stage in its effect. At the viscous stage, the mass concentration at the head was no longer present, and the velocity oscillations also decreased.

Inducible Nitric Oxide Synthase Embedded in Alginate/Polyethyleneimine Hydrogel as a New Platform to Explore NO-Driven Modulation of Biological Function.

Nitric oxide (NO), a small free radical molecule, turned out to be pervasive in biology and was shown to have a substantial influence on a range of biological activities, including cell growth and apoptosis. This molecule is involved in signaling and affects a number of physiologic functions. In recent decades, several processes related to cancer, such as angiogenesis, programmed cell death, infiltration, cell cycle progression, and metastasis, have been linked with nitric oxide. In addition, other parallel work showed that NO also has the potential to operate as an anti-cancer agent. As a result, it has gained attention in cancer-related therapeutics. The nitric oxide synthase enzyme family (NOS) is required for the biosynthesis of nitric oxide. It is becoming increasingly popular to develop NO-releasing materials as strong tumoricidal therapies that can deliver sustained high concentrations of nitric oxide to tumor sites. In this paper, we developed NO-releasing materials based on sodium alginate hydrogel. In this regard, alginate hydrogel discs were modified by adsorbing layers of polyethyleneimine and iNOS-oxygenase. These NO-releasing hydrogel discs were prepared using the layer-by-layer film building technique. The iNOS-oxygenase is adsorbed on the positively charged polyethyleneimine (PEI) matrix layer, which was formed on a negatively charged sodium alginate hydrogel. We show that nitric oxide is produced by enzymes contained within the hydrogel material when it is exposed to a solution containing all the components necessary for the NOS reaction. The electrostatic chemical adsorption of the layer-by-layer process was confirmed by FTIR measurements as well as scanning electron microscopy. We then tested the biocompatibility of the resulting modified sodium alginate hydrogel discs. We showed that this NOS-PEI-modified hydrogel is overall compatible with cell growth. We characterized the NOS/hydrogel films and examined their functional features in terms of NO release profiles. However, during the first 24 h of activity, these films show an increase in NO release flux, followed by a gradual drop and then a period of stable NO release. These findings show the inherent potential of using this system as a platform for NO-driven modulation of biological functions, including carcinogenesis.