Cell Number Density Research Articles

Enhanced Cell Growth and Astaxanthin Production in Haematococcus lacustris by Mechanostimulation of Seed Cysts

The slow growth and complex life cycle of Haematococcus lacustris pose significant challenges for cost-effective astaxanthin production. This study explores the use of microfluidic collision treatment to stimulate the germination of dormant seed cysts, thereby improving photosynthetic cell growth and astaxanthin productivity in H. lacustris cultivated in well plate and flask cultures. The flow rate (1.0–3.0 mL/min) and the number of T-junction loops (3–30) were optimized in the microfluidic device. Under optimal conditions (a flow rate of 2.0 mL/min with 10 loops), the total cell number density in well plate cultures increased by 44.5% compared to untreated controls, reaching 28.9 ± 2.0 × 104 cells/mL after 72 h. In flask cultures, treated cysts showed a 21% increase in astaxanthin productivity after 30 d, reaching 0.95 mg/L/d, due to higher biomass concentrations, while the astaxanthin content per cell remained constant. However, excessive physical collision stress at higher flow rates and loop numbers resulted in reduced cell viability and cell damage. These findings suggest that carefully controlled cyst mechanostimulation can be an effective and environmentally friendly strategy for Haematococcus biorefining, enabling the production of multiple bioactive products.

Cytotoxic Effect of Stenotrophomonas maltophilia Isolated from Prostate and Bladder Cancer Patients in Iraq.

This study investigated the cytotoxic effects of Stenotrophomonas maltophilia on normal human cells. Seven isolates of S. maltophilia were obtained from 120 urine samples collected from prostate and bladder cancer patients, with diagnoses confirmed via Vitek. The cytotoxicity of these bacterial isolates was assessed on normal human fibrocyte cells (NHF) using various concentrations of bacterial filtrate (3.125, 6.25, 12.5, 25, 50, and 100 μg/ml). The bacterial filtrate exhibited significant toxicity to NHF cells, with the highest cell death rate of 68% and the lowest optical density (OD) of 0.25 at a concentration of 100 μg/ml. The IC50 value, indicating the concentration at which 50% inhibition of cell viability occurred, was determined to be 49.35 μg/ml. Further research is necessary to explore the potential role of these bacterial isolates in promoting cancer through inflammation. The clinical isolates of S. maltophilia demonstrated substantial cytotoxic activity against normal human fibrocyte cells, leading to a notable reduction in both cell number and optical density, with the highest percentage of cell death observed. These findings suggest the need for further investigation into the specific toxins or enzymes involved, which could pave the way for future studies.

An evaluation of the analytical and biological robustness of a method for quantifying iron in individual red blood cells via single-cell tandem ICP-mass spectrometry

This work evaluated the analytical and biological robustness of iron (Fe) determination in individual red blood cells (RBCs) via single-cell ICP-MS (SC-ICP-MS). RBCs were separated from other whole blood constituents using Ficoll-Paque™ density gradient centrifugation. While fixation with paraformaldehyde (PFA) led to RBC lysis, the use of glutaraldehyde (GA) left the RBCs intact and permitted storage of RBC cell suspensions in ultra-pure water for up to 16 months at 4 °C. GA-fixation also rendered the RBCs sufficiently robust to maintain integrity during their introduction into the ICP by means of nebulization of dilute suspensions. Obtaining quantitative data on a cell-per-cell basis required determination of the transport efficiency using the particle size method and external calibration against aqueous Fe standard solutions. The average Fe content per RBC obtained using SC-ICP-MS (average value of 103 fg/cell) agreed well with the value obtained using solution-based ICP-MS obtained after cell pellet digestion and with values obtained from literature. Variation of the cell number density in the suspensions analyzed between 1.5 × 105 and 6.0 × 105 cells per mL did not affect the result. Identical results from one-week interval blood drawings from healthy individuals demonstrate biological consistency. Compared to bulk analysis, the SC-ICP-MS approach offers the added value of providing information on the cell-to-cell heterogeneity in Fe content.

The Effect of Different Surfactants and Polyelectrolytes on Nano-Vesiculation of Artificial and Cellular Membranes.

Nano- and micro-sized vesicular and colloidal structures mediate cell-cell communication. They are important players in the physiology of plants, animals, and humans, and are a subject of increasing interest. We investigated the effect of three surfactants, N-cetylpyridinium chloride (CPC), sodium dodecyl sulfate (SDS), and Triton X-100 (TX100), and two anionic polyelectrolytes, sodium polystyrene sulfonate (NaPSS) and sodium polymethacrylate (NaPMA), on nanoliposomes. In addition, the effect of SDS and TX100 on selected biological membranes (erythrocytes and microalgae) was investigated. The liposomes were produced by extrusion and evaluated by microcalorimetry and light scattering, based on the total intensity of the scattered light (Itot), hydrodynamic radius (Rh), radius of gyration (Rg), shape parameter p (=Rh/Rg,0), and polydispersity index. The EPs shed from erythrocytes and microalgae Dunaliella tertiolecta and Phaeodactylum tricornutum were visualized by scanning electron microscopy (SEM) and analyzed by flow cytometry (FCM). The Rh and Itot values in POPC liposome suspensions with added CPC, SDS, and TX100 were roughly constant up to the respective critical micelle concentrations (CMCs) of the surfactants. At higher compound concentrations, Itot dropped towards zero, whereas Rh increased to values higher than in pure POPC suspensions (Rh ≈ 60-70 nm), indicating the disintegration of liposomes and formation of larger particles, i.e., various POPC-S aggregates. Nanoliposomes were stable upon the addition of NaPSS and NaPMA, as indicated by the constant Rh and Itot values. The interaction of CPC, SDS, or TX100 with liposomes was exothermic, while there were no measurable heat effects with NaPSS or NaPMA. The SDS and TX100 increased the number density of EPs several-fold in erythrocyte suspensions and up to 30-fold in the conditioned media of Dunaliella tertiolecta at the expense of the number density of cells, which decreased to less than 5% in erythrocytes and several-fold in Dunaliella tertiolecta. The SDS and TX100 did not affect the number density of the microalgae Phaeodactylum tricornutum, while the number density of EPs was lower in the conditioned media than in the control, but increased several-fold in a concentration-dependent manner. Our results indicate that amphiphilic molecules need to be organized in nanosized particles to match the local curvature of the membrane for facilitated uptake. To pursue this hypothesis, other surfactants and biological membranes should be studied in the future for more general conclusions.

Membrane potential as master regulator of cellular mechano-transduction.

Membrane potential is a property of all living cells 1 . Nevertheless, its physiological role in non-excitable cells is poorly understood. Resting membrane potential is typically considered fixed and under tight homeostatic control 2 . Contrary to this paradigm, we find that membrane potential is a dynamic property that directly reflects mechanical forces acting on the cell and that cells use membrane potential to assess their biomechanical state. We show that several important mechano-sensitive signal transduction pathways, like MAPK and Hippo 3-9 , are directly controlled by membrane potential and this signaling is mediated by upstream membrane-bound receptors, including FAT1. We further show that mechano-transduction via membrane potential plays a critical role in the homeostasis of epithelial tissues, setting cellular biomass density and cell number density by controlling proliferation and cell elimination. In epithelial scratch wound assays, as well as Xenopus tadpole tail regeneration, we observe a wave of depolarization caused by a drop in cellular biomass density due to mechanical stretch and we show that this depolarization wave is critical for wound closure. Together, these data are explained by a first-principles biophysical model, which demonstrates that membrane potential is physically coupled to mechanical pressure and cellular biomass density. Membrane potential thereby provides a quasi-instantaneous, global readout of the biophysical state of the cell and in turn regulates cell growth, resulting in homeostatic feedback control of biomass density and cell number density in tissues. This interplay may be an ancient mechanism for growth control in multi-cellular organisms and its misregulation may play an important role in tumorigenesis.

Insights into heterogeneous surface induced bubble nucleation mechanisms in cellulose reinforced polylactic acid foams

As the most abundant natural homo-polymer, cellulose has the potential to enhance polymer properties reducing the cost of raw materials. In this work, the carboxylate cellulose nanofiber (CNF-C) was selected to modify polylactic acid (PLA) foams, and the density functional theory was constructed to help analyze the foaming mechanism quantitatively. The theoretical results showed that the ordered structure, the carboxyl and the hydroxyl of CNF-C were more conducive to providing much stronger CO2 adsorption for bubble nucleation, where the predicted critical bubble size decreased and the cell density increased with the addition of CNF-C. The experimental results revealed that the CNF-C promoted the rheological properties and crystallization behaviors of PLA samples, the PLA/CNF-C foams were characterized with uniform structures, the average cell size decreased from 21.39 μm to 0.19 μm, and the cell number density increased from 2.65×1010cell/cm3 to 2.30×1014cell/cm3. Those improvements resulted in an increase of 394.0 % for the compressive strength of the prepared foams. Generally, the high-performance PLA/CNF-C foams were fabricated successfully without compromising the properties of bio-based and biodegradable, the foaming mechanism was analyzed combining theoretical results with experimental data, and it was believed to provide a guide for cellulose reinforcing biodegradable polymer materials.

A Vicsek-type model of confined cancer cells with variable clustering affinities.

Clustering of cells is an essential component of many biological processes from tissue formation to cancer metastasis. We develop a minimal, Vicsek-based model of cellular interactions that robustly and accurately captures the variable propensity of different cells to form groups when confined. We calibrate and validate the model with experimental data on clustering affinities of four lines of tumor cells. We then show that cell clustering or separation tendencies are retained in environments with higher cell number densities and in cell mixtures. Finally, we calibrate our model with experimental measurements on the separation of cells treated with anti-clustering agents and find that treated cells maintain their distances in denser suspensions. We show that the model reconstructs several cell interaction mechanisms, which makes it suitable for exploring the dynamics of cell cluster formation as well as cell separation. Insight: We developed a model of cellular interactions that captures the clustering and separation of cells in an enclosure. Our model is particularly relevant for microfluidic systems with confined cells and we centered our work around one such emerging assay for the detection and research on clustering breast cancer cells. We calibrated our model using the existing experimental data and used it to explore the functionality of the assay under a broader set of conditions than originally considered. Future usages of our model can include purely theoretical and computational considerations, exploring experimental devices, and supporting research on small to medium-sized cell clusters.

Foam stability and thermo-mechanical properties of micro/nano filler loaded castor oil based flexible polyurethane foam

Use of fillers in polymers is to improve thermo-mechanical properties of the resulting material. Fillers are also used in polymeric foam as cell openers. Flexible polyurethane (PU) foams undergo major loss in structural stability when synthetic polyol is replaced with castor oil in the formulation as an alternate polyol. This study probes the effect of various micro and nano-fillers on PU foams prepared using blend polyol containing castor oil and synthetic polyol at a ratio of 1:1. Physical and cellular properties such as foam height, cell diameter, strut thickness and cell number density were evaluated to probe the structural stability of the foam. All foams prepared were found stable while it was found that the densities of the PU foams synthesized were greater than that of the conventional PU foams. Addition of fillers found to enhance thermal and mechanical properties of the foam. Moreover, all foam samples were found to observe thermal stability over and above 258 °C. Minimum glass transition temperature was recorded for 15% HG samples (i.e., −35.5 °C). Highest tensile strength was observed for 15% Si samples whereas, highest elongation was observed for 10% NC.

Circular Reprocessing of Thermoset Polyurethane Foams.

Thermoset polyurethane (PU) foams are widely used in industrial applications, but they cannot be recycled by conventional melt reprocessing because of their cross-linked structures. The introduction of carbamate exchange catalysts converts thermoset PU into covalent adaptable networks (CANs), which are amenable to reprocessing at elevated temperatures. However, this approach has produced solid PU films, which have fewer uses and lower commercial demand. In this work, simultaneous reprocessing and refoaming of thermoset PU foams is demonstrated by leveraging the melt-processability of PU CANs and allowing cell growth by gas generation in a twin-screw extruder. The optimal operating temperature of the refoaming process is determined through chemical, thermal, and structural analysis of PU foam extrudates. The foam-to-foam extrusion process produces controllable, continuous, and uniform foam structures, as characterized by cell diameter and cell number density. Low-density PU foams are obtained through a process simulating injection molding. The compression properties of reprocessed PU foam are compared with as-synthesized PU foam to demonstrate efficacy of the refoaming processes. These results demonstrate that PU foams can be prepared through recycling while maintaining microstructural and chemical integrity. In the future, this strategy may be applied to thermoset PU foams of various chemical compositions and shows promise for scalability.

Excessive dietary soluble arabinoxylan impairs the intestinal physical and immunological barriers via activating MAPK/NF-κB signaling pathway in rainbow trout (Oncorhynchus mykiss)

Arabinoxylan (AX) has been deemed as an antinutritional factor, but limited information has addressed the effects of dietary AX on intestinal health of fish. The present study investigated the effects of dietary AX on intestinal mucosal physical and immunological barriers of rainbow trout (Oncorhynchus mykiss). Five isoproteic and isolipidic experimental diets (AXE, AX0, AX2.5, AX5 and AX10) were formulated to contain 0.03% arabinoxylanase as well as 0%, 2.5%, 5% and 10% AX, respectively. Each diet was randomly distributed to triplicate groups of 35 juvenile (average weight 3.14 ± 0.02 g) per tank in a rearing system maintained at 17 ± 1 °C for 9 weeks. Dietary AX supplementation regardless of inclusion levels significantly (P < 0.05) depressed the growth performance and feed utilization. The plasma endothelin-1 and d-lactic acid contents as well as diamino oxidase activity were significantly higher in fish fed diet AX10 compared to fish fed diet AX0. Dietary inclusion of 5–10% AX resulted in decreased intestinal villus height, goblet cell number and desmosome density, increased crypt depth, short and irregular microvilli, widened intercellular space; down-regulated the mRNA levels of occludin in hindgut, claudin3 and ZO-1 in foregut and midgut, but up-regulated the mRNA levels of claudin12 and claudin15 in midgut as well as claudin23 in foregut, midgut and hindgut. Furthermore, dietary 5–10% AX supplementation decreased the midgut and hindgut complement 3, complement 4 and sIgT contents as well as the midgut IgM and hindgut IL-10 contents. Conversely, the hindgut TNF-α and IL-6 contents increased with the rising dietary AX level. RT-qPCR demonstrated that the pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IL-12β, IFN-γ, and TNF-α) and pIgR mRNA levels in midgut and hindgut were up-regulated by dietary AX inclusion of 5–10% AX. Meanwhile, the mRNA levels of p38 MAPK, IκBα, and NF-κB p65 in midgut and hindgut raised gradually with the increasing dietary AX content. The Western blot results showed that the protein expression levels of p38 MAPK and NF-κB generally increased with the rising dietary AX content. Dietary treatment with 0.03% arabinoxylanase did not affect the growth performance and intestinal health of rainbow trout (P > 0.05). In conclusion, excessive dietary AX inclusion (5–10%) increased the intestinal permeability and induced the intestinal inflammatory response via activating MAPK/NF-κB signaling pathway, and ultimately damaged the intestinal barrier function of rainbow trout.

Gas foaming of polyphenyl sulfone: Effect of the blowing agents and operating parameters

AbstractPolyphenyl sulfone (PPSU) is a highly stable and rigid polymer with good chemical and mechanical resistance used in automotive and aerospace industries in high‐temperature applications during long‐operating cycles. PPSU foams are applied as core materials in lightweight composites ensuring high strength, fire resistance, thermal and acoustic insulation. In this paper, PPSU slabs are foamed using CO2, N2, and He as blowing agents (BAs). An experimental campaign is carried out to estimate the BAs' diffusivity in the polymer. In details, CO2 diffusivity ranges from 8E‐11 to 1E‐09 m2/s at temperatures from 220 to 260°C; diffusivity of N2 ranges from 2E‐10 to 5E‐09 m2/s (220–260°C) and it is 4E‐09 m2/s for He at 220°C. Foaming tests reveal an expansion ratio as high as 400% for CO2, 130% for He, and 150% for N2.Scanning electron microscopy analysis is also performed on produced samples, obtaining a cell number density of 1.3E07, 2.6E05, and 1.8E06 cells/cm3 when saturating, respectively, with CO2 at 220°C and 100 bar, N2 at 220°C and 100 bar, and He at 230°C and 100 bar.

Expression of early growth responsive gene-1 in the lateral geniculate body of kittens with amblyopia caused by monocular form deprivation.

The expression of early growth responsive gene-1 (Egr-1) in the lateral geniculate body in the normal kittens and those affected with amblyopia caused by monocular visual deprivation was compared to explore the potential significance of Egr-1 in the pathogenesis of amblyopia. A total of 30 healthy kittens were equally and randomly divided into the control (n = 15) and the deprivation group (n = 15). The kittens were raised in natural light and the right eyes of the deprived kittens were covered with a black opaque covering. Pattern visual evoked potential (PVEP) was measured before and 1, 3, and 5 weeks after covering. Five kittens from each group were randomly selected and euthanized with 2% sodium pentobarbital (100 mg/kg) during the 1st, 3rd and 5th week after covering. The expression of Egr-1 in the lateral geniculate body in the two groups was compared by performing immunohistochemistry and in situ hybridization. After three weeks of covering, PVEP detection indicated that the P100 wave latency in the deprivation group was significantly higher than that in the control group (P < 0.05), whereas the amplitude decreased markedly (P < 0.05). The number of the positive cells (P < 0.05) and mean optical density (P < 0.05) of Egr-1 protein expression in the lateral geniculate body of the deprivation group were found to be substantially lower in comparison to the normal group, as well as the number (P < 0.05) and mean optical density of Egr-1 mRNA-positive cells (P < 0.05). However, with increase of age, positive expression of Egr-1 in the control group showed an upward trend (P < 0.05), but this trend was not noted in the deprivation group (P > 0.05). Monocular form deprivation can lead to substantially decreased expressions of Egr-1 protein and mRNA in the lateral geniculate body, which in turn can affect the normal expression of neuronal functions in the lateral geniculate body, thereby promoting the occurrence and development of amblyopia.

Роль тучных клеток в прогрессировании контрактуры Дюпюитрена

Introduction World literature data indicate the involvement of mast cells in the pathogenesis of Dupuytren's disease. There is no information on the content of mast cells in the pathologically altered palmar fascia of patients depending on the severity of the contracture. Purpose To study changes in the number, location and degranulation activity of mast cells in the palmar aponeurosis with Dupuytren's contracture of varying severity. Material and methods Histopathological study of surgical material from 52 patients (49 men and 3 women) with Dupuytren's contracture (age range 35-78 years, mean age 59.12 ± 1.25 years) using histomorphometry of epoxy semi-thin sections stained with methylene blue – the main fuchsin. Patients were divided into two groups: group 1 with 1‑2 (n = 16) and group 2 with 3-4 (n = 36) grades of the contracture. Results In group 2, the location of mast cells among contractilely altered collagen fibers of dense connective tissue was recorded more often than in group 1. In group 2, compared with group 1, the following significantly increased: the median number density of mast cells – by 33.79 % (p = 0.0508), the median area of mast cells – by 48.40 % (p = 0.0008) and the index mast cell degranulation – by 94.68 % (p = 0.00000001). Discussion Along with a change in the typical location of mast cells, objective evidence of an increase in their number, activation and degranulation in patients with severe contractures was obtained. Conclusion The obtained results indicate the role of mast cells in the progression of Dupuytren's contracture and expand the understanding of potential therapeutic targets.

Morphofunctional Changes in Neurons, Glial Cells and Synapses in the Sensorimotor Cortex after Severe Traumatic Brain Injury

The aim of the study was to investigate morphofunctional modifications in neurons, glial cells and synaptic terminals in the sensorimotor cortex of the brain in rats after severe traumatic brain injury (STBI).Material and methods. STBI simulation in white rats (main group, n=30) was performed on a device with a special shock mechanism. Intact animals (n=6) were included in the control group. The sensorimotor cortex (SMC) of the brain in rats was studied histomorphologically on sections stained with hematoxylin and eosin and thionin according to Nissl. Synaptophysin and GFAP were detected immunohistochemically, then morphometry was performed. On serial frontal sections of the SMC, neurons, neuroglia, and interneuronal synapses were studied in animals of the control group and in animals exposed to STBI in 1, 3, 7, 14, and 30 days after STBI simulation. The number density of neurons, neuroglia, and synaptic terminals was determined per a unit area of the section of layers I (terminals only), III, and V of the cerebral SMC. Statistical hypotheses were tested using nonparametric methods in the Statistica 10.0 program.Results. In animals of the control group, typical normochromic pyramidal neurons predominated, synaptic terminals were clearly verified; this was combined with unaltered neuropil. In animals exposed to STBI, there were signs of tinctorial, hydropic, dehydration and necrobiotic changes in neurons, reactive astrogliosis, fields of "loss" of neurons appeared; the overall numerical density of neurons and synapses decreased. The maximally increased content of pycnomorphic neurons was detected in 1 day after STBI (in layer III of the SMC, by 11.6%; in layer V of the SMC, by 18.5%). The peak in the number density of shadow cells and hyperchromic non-wrinkled neurons was noted in 3 days. The numerical density of synaptic terminals in different layers of the SMC decreased by 1.5-2 times. The altered balance of the destruction and restoration processes of the synaptic pool after STBI was evidenced by statistically significant data on the decreased and increased numerical density of terminals during 30 days of the study. There was no complete recovery of the studied parameters of neurons and synapses to control values within 30 days.Conclusion. The SMC of the brain in rats remains functioning after STBI; this occurs in the context of long-term preservation of reversibly and irreversibly damaged neurons, reactive neurogliosis, and permanent reorganization of interneuronal relationships due to activated reparative neuro- and synaptic plasticity. The data obtained will specify reorganization of the components of various neuronal complexes of the SMC (layers I, III, and V) after STBI.

Fabrication and properties of natural rubber/rice starch/activated carbon biocomposite-based packing foam sheets and their application to shelf life extension of ‘Hom Thong’ banana

Natural rubber (NR) and rice starch (RS) biocomposite-based packing foam sheets were successfully prepared by the Dunlop method, with activated carbon (AC) as a filler to enhance mechanical properties (and to absorb ethylene gas released by packaged bananas). The primary objective of this study was to examine the influences of activated carbon contents from 0 to 20 phr on physical, morphological, mechanical, and thermal properties of the biocomposite foams. With increasing AC content, the foam cell size, density, hardness, compression force deflection (CFD), compression set, tensile strength, elongation at break, tear strength and glass transition temperature (Tg) increased, while the number density of foam cells and rebound resilience decreased. However, the content of activated carbon did not affect the thermal stability. Furthermore, the developed biocomposite foam with 15 phr AC, which had the highest ethylene removal, was used to evaluate the ethylene absorption capacity and the quality of 'Hom Thong' bananas during 12 days of storage in terms of weight loss, pulp firmness, total soluble solids (TSS), physical appearance, and peel color, with comparison to a commercial foam and control. The biocomposite foam with 15 phr AC lowered the ambient ethylene levels considerably, hence delaying fruit ripening and decreasing chlorophyll degradation, TSS, and pulp firmness at 6 days of ambient storage. The proposed biocomposite foam shows potential for enhancing the postharvest storage stability of bananas and has great potential as packaging for other fresh fruit products.

Microencapsulation of Lactobacillus plantarum 299v Strain with Whey Proteins by Lyophilization and Its Application in Production of Probiotic Apple Juices

The viability of probiotics is strictly influenced by the production, storage, and digestion, while microencapsulation is a technology that can protect them against harsh environments. In this study, the impact of different core-to-wall ratios and wall material formulations on physical properties and the cell number of the microcapsules were investigated. The samples with core-to-wall ratio 1:1 have a significantly higher cell number, encapsulation efficiency, and bulk density than samples with core-to-wall ratio 1:1.5. The yields of the encapsulation method were changes in the opposite direction. Meanwhile, core-to-wall ratios and formulation have a significant effect on the cell number of the microcapsules during the in vitro SGJ test, whereas time, core-to-wall ratios, and formulation have a similar influence in the in vitro SIJ test. Moreover, probiotic apple juices stored at 4 °C for 6 weeks kept the highest cell number at the end. Furthermore, probiotic apple juices fortified by microcapsules coated with WP:DWP 1:1 in core-to-wall ratio 1:1 and stored at 4 °C for 4–8 weeks exhibited a significantly lower pH value. In summary, both whey proteins and denatured whey proteins are as good as coating material for microencapsulation of probiotic bacteria Lactobacillus plantarum 299v strains. These microcapsules have high potential in the production of probiotic apple juice even by fermentation or fortification methods.

Monolithic integrated micro-supercapacitors with ultra-high systemic volumetric performance and areal output voltage.

Monolithic integrated micro-supercapacitors (MIMSCs) with high systemic performance and cell-number density are important for miniaturized electronics to empower the Internet of Things. However, fabrication of customizable MIMSCs in an extremely small space remains a huge challenge considering key factors such as materials selection, electrolyte confinement, microfabrication and device-performance uniformity. Here, we develop a universal and large-throughput microfabrication strategy to address all these issues by combining multistep lithographic patterning, spray printing of MXene microelectrodes and controllable 3D printing of gel electrolytes. We achieve the monolithic integration of electrochemically isolated micro-supercapacitors in close proximity by leveraging high-resolution micropatterning techniques for microelectrode deposition and 3D printing for precise electrolyte deposition. Notably, the MIMSCs obtained demonstrate a high areal-number density of 28 cells cm-2 (340 cells on 3.5×3.5cm2), a record areal output voltage of 75.6V cm-2, an acceptable systemic volumetric energy density of 9.8 mWh cm-3 and an unprecedentedly high capacitance retention of 92% after 4000 cycles at an extremely high output voltage of 162V. This work paves the way for monolithic integrated and microscopic energy-storage assemblies for powering future microelectronics.

A period of transient synaptic density unbalancing in the motor cortex after peripheral nerve injury and the involvement of microglial cells

Some types of peripheral nerve injury lead to limb deafferentation, which leads to remodeling of body representation areas in different parts of the brain, such as in the primary motor cortex and primary sensory cortex. This plasticity is a consequence of several cellular events, such as the emergence and elimination of synapses in these areas. Beside neurons, microglial cells are intimately involved in synapse plasticity, especially in synaptic pruning. In this study, we investigated the transient changes in synaptic density in the primary motor and sensory cortex after different types of peripheral nerve injury, as well as the behavior of microglial cells in each scenario. Male C57/B6 mice were divided into a control group (no injury), sciatic-crush group, and sciatic-transection group, and treated with PBS or minocycline daily for different time points. Both types of sciatic lesion led to a significant decrease of synaptophysin and PSD-95 positive puncta counts compared to control animals 4 days after lesion (DAL), which recovered at 7 DAL and was sustained until 14 DAL. The changes in synaptic puncta density were concomitant with changes in the density and morphology of microglial cells, which were significantly more ramified in the primary motor cortex of injured animals at 1 and 4 DAL. Although the decreased synaptic puncta density overlapped with an increased number of microglial cells, the number of lysosomes per microglial cell did not increase on day 4 after lesion. Surprisingly, daily administration of minocycline increased microglial cell number and PSD-95 positive puncta density by 14 DAL. Taken together, we found evidence for transient changes in synaptic density in the primary motor, related to peripheral injury with possible participation of microglia in this plasticity process.

Two-Stage Structural and Slowing-Down Percolation Transitions in the Densifying Cancer Cell Monolayer.

We experimentally demonstrate the two-stage structural and slowing-down percolating transitions, followed by the confluent transition in the densifying cancer cell monolayers from the dilute state, and investigate their impacts on collective cell dynamics. It is found that cells aggregate into clusters at low cell density. With increasing cell number density, the structural percolation through the formation of a large cell cluster percolating through the space precedes the dynamical percolation transition of forming a percolating cluster of slow cell elements. Both percolating transitions exhibit scale-free scaling behaviors of cluster size distributions and fractal structures, similar to those of the universality class of 2D nonequilibrium systems governed by percolation theory. Dynamically, at low cell density, cell aggregation enhances cooperative motion. The structural percolation leads to slower motion, especially with stronger suppression for the high-frequency modes in the turbulent-like velocity power spectra. The following slowing-down percolation associated with the onset of cell crowding in regions occupied by cells further enhances dynamical slowing-down, and suppresses the increasing trend of dynamical heterogeneity and the steepening of the power spectrum of motion, until their reversions after the confluent transition.

Is the Pinus massoniana Lamb. Tree-Ring Latewood Formation Influenced by the Diurnal Temperature Range in Humid Subtropical China?

Tree-ring latewood is a key proxy for the reconstruction of climate, especially for temperature. The mechanisms of latewood formation and its responses to climates remain uncertain. Given that the tree-ring latewood of the taproot is absent belowground under conditions of low temperature gradients, we thus hypothesize that low diurnal temperature ranges (DTRs) may be one determining factor for latewood production. To evaluate this hypothesis, we designed experimental investigations by adding heat-protecting layers to the trunks of Pinus massoniana Lamb. to lower DTRs and simulate the environmental conditions underground in the Fuzhou area of humid subtropical China (HSC). We found that a decreased DTR induces a significant decline in latewood cell thickness and a slight reduction in latewood cell number and latewood density. DTRs played an important role in the formation of tree-ring width (TRW) and latewood width (LWW) rather than precipitation. Our study highlighted the effects of DTRs on tree growth and wood anatomical changes and provided a possible explanation for the “divergence problem” in dendroclimatology.