Small Drop Research Articles

A-155 Development of drop-of-blood QATT heparinase and functional fibrinogen assays

Abstract Background Monitoring the blood coagulation status of patients with coagulopathy or on anticoagulant therapy is important for informed treatment decisions. Quasi-static acoustic tweezing thromboelastometry (QATT) can monitor changes in blood coagulation using a small blood drop. Here, we develop the heparinase and functional fibrinogen QATT assays. Methods Citrated whole blood (WB) samples were collected from 20 healthy volunteers using IRB-approved protocols No. 520566 and 944474. Half of the samples were used for fibrinogen, platelet count tests and the others were used for QATT measurements. For developing heparinase assay, WB samples from 4 healthy volunteers were randomly selected. For each volunteer sample, QATT experiments were performed for a WB sample, a WB sample spiked with 0.5 IU/mL heparin, and a WB sample spiked with heparin and then heparinase. For developing functional fibrinogen assay, QATT experiments were performed for a WB sample and a WB sample spiked with Cytochalasin-D (4 μM). Coagulation was triggered via intrinsic pathway. Pearson correlation coefficient (rp) or the Spearman rank correlation coefficient (rs) was used for correlation analysis. We focused on the following QATT parameters: CIT, MCF, and MCE. Results The heparinase assay effectively reversed heparinized samples (Fig. 1a). CIT of normal and heparinized samples treated with heparinase were within reference range (Fig. 1b). The effect of Cytochalasin-D was shown in Fig 1c. Strong correlation was found between MCE of Cyto-treated WB and fibrinogen level (rp = 0.75). MCE of the difference between normal and Cyto-treated WB, referred to as MCEplatelet, was also strongly correlated with platelet count test (rs = 0.76). The normal range for MCF of the functional fibrinogen assay is efficient in ruling out abnormal fibrinogen level (Fig. 1d). Conclusions QATT accurately predicted the inhibition of heparin by heparinase. QATT functional fibrinogen assay detected the contribution of both fibrinogen and platelets to the clot strength.

Improving multi-object detection and tracking with deep learning, DeepSORT, and frame cancellation techniques

Abstract Multi-object detection and tracking is a crucial and extensively researched field in image processing and computer vision. It involves predicting complete tracklets for many objects in a video clip concurrently. This article uses the frame cancellation technique to reduce the computation time required for deep learning and DeepSORT (for any version of the YOLO detector) coupled with DeepSORT algorithm techniques. This novel technique implements a different number of frame cancellations, starting from one frame and continuing until nine frame cancellations, tabling the result of each frame cancellation against the overall system performance for each frame cancellation. The proposed method worked very well; there was a small drop in the average tracking accuracy after the third frame rate cancellation, but the execution time was much faster.

Study the Physiological Effects of Palm Heart Extract (PHE) on some Cardiac, Hepatic Enzymes, and Reproductive Hormones in Male Rats

Background: For a long time, researchers have extensively studied the health advantages of natural products derived from plants. Objective: The main goal of this study is to investigate the effects of palm heart extract (PHE) on the lipid profile and various parameters of the heart, liver, and reproductive system in male rabbits. Methods: The male rabbits were divided into four groups by chance; one group was given a standard diet for comparison, while the other three received a PHE supplement. The control group did not get any treatment while three groups were given medium to high doses of PHE daily for 8 weeks. Troponin and lipid profile levels were assessed for health indicators, while liver enzyme levels (ALT, AST, ALP) and total bilirubin were analyzed to evaluate liver function. Furthermore, hormone levels such as testosterone, LH (luteinizing hormone), and FSH (follicle stimulating hormone) were also observed during the entire study period. Outcomes: Lipid profile parameters, including cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL), and high density lipoprotein cholesterol (HDL), were assessed before and after the intervention period. Results: The results indicated a reduction in TC and LDL levels in the treatment group compared to the control group was statistically significant (p < 0.05). Nonetheless, there were no changes observed in the levels of TG and HDL in both groups, with a p-value greater than 0.05. These results indicate that heart palm water extract might have the ability to lower lipid levels, especially in decreasing total cholesterol and LDL levels. Testosterone levels showed a small drop in the high dose group when compared to the control group, although there was no statistical significance (p > 0.05). LH levels did not significantly decrease in the medium dose group compared to the control group (p < 0.05). There were no notable variations in FSH levels among the groups (p < 0.05). In conclusion, male rabbits showed reduced troponin levels in a dose-dependent manner, indicating potential cardioprotective effects of HDP extract. The administration of HDP extract did not have any impact on liver function. Although reproductive hormone levels varied, additional research is required to understand the effects of heart palm extract on male reproductive health.

A Small Electrolyte Drop Enables a Disruptive Semisolid High‐Energy Sulfur Battery Cell Design via an Argyrodite‐Based Sulfur Cathode in Combination with a Metallic Lithium Anode

AbstractLithium–sulfur batteries with liquid electrolytes are discussed as the most promising post‐lithium‐ion‐battery technology in literature due to their high theoretical specific energy and first prototype cells delivering >470 Wh kg−1. Although several electrolyte and material concepts are developed that partially solve the issue of the so‐called shuttle mechanism, the most promising concept to genuinely confine sulfur species in the cathode is all‐solid‐state argyrodite–sulfur cathodes leading to almost theoretical active material utilization by maintaining reasonable sulfur loadings and electrolyte to sulfur ratios. However, this battery concept has so far not achieved reversible cycling against metallic lithium anodes as it requires high pressures for manufacturing, and ductile lithium metal creeps along the grain boundaries of the solid electrolyte particles leading to short cuts of the cells. Recent findings show that metallic lithium, however, can be stably cycled with dimethoxyethane/lithium‐bis(fluorosulfonyl)imide (DME/LiFSI)‐based electrolytes. Herein, for the first time, a semisolid concept is presented combining the benefits of an argyrodite‐based solid‐state cathode and a DME/LiFSI/hydrofluoroether‐based anolyte concept – in coin cells and first pouch cells. This disruptive approach enables projected specific energies higher than 600 Wh kg−1 at cell stack level.

Effect of temperature on the stability and performance of III-nitride HEMT magnetic field sensors

The study aimed to investigate the underlying physics limiting the temperature stability and performance of non-surface passivated Al0.34Ga0.66N/GaN Hall effect sensors, including contacts, under atmospheric conditions. The results obtained from analyzing the microstructural evolution in the Al0.34Ga0.66N/GaN Hall sensor heterostructure were found to correlate with the electrical performance of the Hall effect sensor. High-resolution x-ray photoelectron spectroscopy studies revealed the signature of surface oxidation in the GaN cap layer, as well as a slight out-diffusion of “Al” from the AlGaN barrier layer. To prevent the formation of a bumpy surface morphology at the Ohmic contact, we investigated the impact of “Pt” top Ohmic contacts. The application of a top “Pt” contact stack resulted in a smooth Ohmic contact surface and provided evidence that the bumpy surface morphology in Au-based Ohmic contacts is due to the formation of an Al-Au viscous alloy during rapid thermal annealing. In the early stages of thermal aging, the small drop in contact resistivity stabilized with subsequent thermal aging past the initial 550 h at 200 °C. The outcome is that the Al0.34Ga0.66N/GaN Hall effect sensors, even without surface passivation, exhibited a stable response to applied magnetic fields with no sign of significant degradation after 2800 h of thermal aging at 200 °C under atmospheric conditions. This observed stability in the Hall sensor without surface passivation can be attributed to a self-imposed surface oxidation of the cap layer during the early stages of aging, which serves as a protective layer for the device during subsequent extended periods of thermal aging at 200 °C.

A parameter design method of LC filter circuit for closed‐loop dynamic power supply system based on linear power amplifier

AbstractThe linear power amplifier (LPA) suffers from low power supply utilization in the DC power supply mode, leading to reduced output efficiency. This paper constructs an efficient power supply mode based on closed‐loop dynamic power supply system (CLDPSs). The CLDPSs can generate a pair of bipolar dynamic power supplies based on a predetermined signal to provide power to LPA, which can maintain a small voltage drop between the power supply and the output of LPA, thereby improving the power supply utilization of LPA. In addition, the study also focuses on the conflicting relationship between the output ripple and the dynamic performance of the CLDPSs, for which a new parametric design of the LC filter circuit is proposed, aiming to achieve a balance between these two aspects. Finally, a voice coil motor driving platform is constructed for experimental testing. The results demonstrate that the output ripple and dynamic performance of the CLDPSs can be balanced. In comparison to the DC power supply mode, the CLDPSs power supply mode can enhance the efficiency of LPA by 2 times while the driving accuracy of voice coil motor is basically unchanged.

Investigation of mixing and heat transfer characteristics of long-hole SK direct contact heat exchanger

In this study, in order to improve the efficiency of direct contact heat exchanger (DCHE), SK static mixers with different perforation index (PI) were applied. Numerical simulation (volume of fluid model) were used to investigate the performance of the static mixer, which shape was designed as long-holes, under fixed aspect and helical ratios. The feasibility and accuracy of numerical simulation results were verified by self-established direct contact heat transfer (DCHT) experimental platform. Under six different PI values (0 %, 10 %, 18 %, 26 %, 32 %, and 38 %), the heat transfer performance of DCHE was evaluated by applying two heat transfer mediums (THERMINOL62 and R141b). The results indicated that the gaseous working medium outlet temperature, turbulence intensity, turbulence kinetic energy, and volumetric heat transfer coefficient (VHTC) of the system showed an increasing trend as PI increased from 0 % to 32 %, then a decreasing trend can be observed from 32 % to 38 %. The maximum turbulence intensity and turbulence kinetic energy of 17.56 % and 0.015 m2/s2 can be found in PI = 32 %, as well as a maximum enhancement ratio of 49 % in VHTC compared to PI = 0 % can be achieved. In addition, only a small pressure drop increase is observed in PI = 32 % compared to PI = 0 %.

First Report of Clonostachys rosea Causing Bulb Rot on Fritillaria taipaiensis in China.

Taibai Beimu (Fritillaria taipaiensis) is a species of Fritillaria commonly used in traditional Chinese medicine for its antitussive, expectorant, and antihypertensive properties. In April of 2021 and 2022, an incidence 10-30% of yellowing or purpling, wilting, and dying symptoms was observed on Taibai Beimu in Wanyuan, Sichuan province. Infected roots and bulbs displayed spots ranging from brown to black, along with necrotic rot. In severe cases, the entire bulbs rotted. Fifteen symptomatic bulbs were cut into 0.5 × 0.5 cm pieces, surface sterilized in 75% ethanol for 30 s and 1% sodium hypochlorite for 3 min under aseptic conditions, rinsed with sterile water 3 times, and air-dried. The segments were placed on potato dextrose agar (PDA) and incubated at 25℃ for 7 days in the dark. Six Clonostachys-like monospore isolates were obtained. Colonies on PDA reached 32 to 43 mm in diameter in 7 days at 25℃ in the dark, felty to tomentose to granulose aerial mycelia with a white or light yellow appearance, and reverse colors matching. On cornmeal-dextrose agar, primary conidiophores had a Verticillium-like structure with 1 to 3 levels. Stipes were 36.1 to 236.3μm long. Phialides formed in whorls of 2 to 5, 15.3 to 45.7μm long, 1.1 to 3.4μm wide at the base, and 1.03 to 2.41μm wide near opening (n=95). Each producing a small hyaline drop of conidia. Conidia were 3.7 to 11.3μm × 2.1 to 4.1μm (n=110). Secondary conidiophores displayed Penicillium-like structures, and stipes were 23.1 to 142.3μm long. Phialides formed in compressed whorls of 4 to 8 per metula, 7.0 to 16.0μm in length, 1.3 to 3.1μm in width at the base, 1.8 to 3.6μm at the widest point, and 0.8 to 1.8μm near opening (n=50). Conidia were 3.0 to 6.4μm ×1.6 to 3.4μm (n=65). The morphology was consistent with the previous description of Clonostachys rosea (Hans-Josef et al. 1999). The ATP citrate lyase (ACL1), β-tubulin (TUB2), translation elongation factor 1-α (tef1α), and the nuclear ribosomal internal transcribed spacer (ITS) of three strains were amplified and sequenced using primers acl1-230up/acl1-1220low (Gräfenhan et al. 2011), T1/CYLTUB1R (Crous et al. 2004; O'Donnell and Cigelnik 1997), EF1-728F/EF2 (Carbone and Kohn 1999; O'Donnell et al. 1998), and ITS1/ITS4 (White et al. 1990), respectively. Blastn homology search showed a > 97% similarity to the ex-type strains of C. rosea (CBS710.86). All sequences have been deposited in GenBank (PP394342 to PP394350, and PP396901 to PP396903). A phylogenetic tree was constructed using Bayesian analysis based on the alignment of the combined ACL1, TUB2, tef1α, and ITS sequences through IQ-TREE. The tree displayed clustering with known strains of C. rosea. Pathogenicity was confirmed by inoculating five healthy five-year-old Taibai beimu plants with a spore suspension (1.0 × 106 spores mL-1) of the strain WYEB1101, while sterilized water was used as a control. The inoculation process involved pouring the spore suspension over the wounded bulbs and covering with them sterile soil. Subsequently, all plants were cultivated in sterile soil indoors under natural conditions suitable for Taibai beimu. The pathogenicity assays were repeated twice. After 20 days of cultivation, the infected plants displayed symptoms similar to those observed in the field, while all control plants remained asymptomatic. Sequencing confirmed the re-isolation of C. rosea from the inoculated plants, satisfying Koch's hypothesis. Clonostachys rosea has been previously reported to cause root rot of Chinese medicine herb, such as Astragalus membranaceus and Gastrodia elata (Lee et al. 2020; Qi et al. 2022). To our knowledge, this is the first report of C. rosea infecting Taibai Beimu in China, highlighting a potential risk to this crop.

Scoring Multi-hop Question Decomposition Using Masked Language Models

Question answering (QA) is a sub-field of Natural Language Processing (NLP) that focuses on developing systems capable of answering natural language queries. Within this domain, multi-hop question answering represents an advanced QA task that requires gathering and reasoning over multiple pieces of information from diverse sources or passages. To handle the complexity of multi-hop questions, question decomposition has been proven to be a valuable approach. This technique involves breaking down complex questions into simpler sub-questions, reducing the complexity of the problem. However, it’s worth noting that existing question decomposition methods often rely on training data, which may not always be readily available for low-resource languages or specialized domains. To address this issue, we propose a novel approach that utilizes pre-trained masked language models to score decomposition candidates in a zero-shot manner. The method involves generating decomposition candidates, scoring them using a pseudo-log likelihood estimation, and ranking them based on their scores. To evaluate the efficacy of the decomposition process, we conducted experiments on two datasets annotated on decomposition in two different languages, Arabic and English. Subsequently, we integrated our approach into a complete QA system and conducted a reading comprehension performance evaluation on the HotpotQA dataset. The obtained results emphasize that while the system exhibited a small drop in performance, it still maintained a significant advance compared to the baseline model. The proposed approach highlights the efficiency of the language model scoring technique in complex reasoning tasks such as multi-hop question decomposition.

Dynamics and active mixing of a droplet in a Stokes trap

Particle trapping and manipulation have a wide range of applications in biotechnology and engineering. Recently, a flow-based, particle-trapping device called the Stokes trap was developed for trapping and control of small particles in the intersection of multiple branches in a microfluidic channel. This device can also be used to perform rheological experiments to determine the viscoelastic response of an emulsion or suspension. We show that besides these applications, the various flow modes produced by the Stokes trap are able to manipulate drop shapes and induce active mixing inside droplets. To this end, we analyse the dynamics of a droplet in a Stokes trap through boundary-integral simulations. We also explore the dynamic response of drop shape with respect to distinct external flow modes, which allows us to perform numerical experiments such as step strain and oscillatory extension. A linear controller is used to manipulate drop position, and the drop deformation is characterized by a spherical-harmonic decomposition. For small drop deformations, we observe a linear superposition of harmonics, which, surprisingly, seems to hold even for moderate deformations. This result indicates that such a device can be used for shape control of droplets. We also investigate how the different flow modes may be combined to induce mixing inside the droplets. The transient combination of modes produces an effective chaotic mixing, which is characterized by a mixing number. The mixing inside the droplet can be further enhanced for lower viscosity ratios and low, but non-zero capillary number and flow frequencies.

Improvement of sound absorption of porous materials through periodic holes of sinusoidal decreasing profile

Porous materials used in several engineering applications for noise attenuation present poor acoustic performance at low frequencies. In this paper, a design of porous materials with various periodic decreasing hole profiles is presented and studied using the finite element method. The sound absorption coefficient and the normalized surface impedance are compared for different periodic decreasing hole profiles. A small drop in sound absorption is observed after the first peak with a decreasing linear profile. Using a sinusoidal decreasing hole profile, it is shown that the drop is attenuated. The impacts of the amplitude and the period of the sinusoidal profile on the sound absorption coefficient and the surface impedance are demonstrated. The proposed porous material design with periodic holes having a sinusoidal decreasing profile shows a significant improvement in sound absorption over a large frequency band compared to conventional porous materials.

Cellulose Nanofiber-Based Triboelectric Nanogenerators for Efficient Air Filtration in Harsh Environments.

Advanced portable healthcare devices with high efficiencies, small pressure drops, and high-temperature resistance are urgently desired in harsh environments with high temperatures, high humidities, and high levels of atmospheric pollution. Triboelectric nanogenerators (TENGs), which serve as energy converters in a revolutionary self-powered sensor device, present a sustainable solution for meeting these requirements. In this work, we developed a porous negative triboelectric material by synthesizing ZIF-8 on the surface of a cellulose/graphene oxide aerogel, grafting it with trimethoxy(1H,1H,2H,2H-heptadecafluorodecyl)silane, and adding a negative corona treatment, and it was combined with a positive triboelectric material to create a cellulose nanofiber-based TENG self-powered filter. The devices achieved a balance between a small pressure drop (53 Pa) and high filtration efficiency (98.97%, 99.65%, and 99.93% for PM0.3, PM0.5, and PM1, respectively), demonstrating robust filtration properties at high temperatures and high humidities. Our work provides a new approach for developing self-powered wearable healthcare devices with excellent air filtration properties.

A modified zeolite (Na2SO4 @zeolite NaA) as a novel adsorbent for radium-226,228 from acidic radioactive wastewater: Synthesis, characterization and testing

The radiological contamination with radium in oil and gas production is challenging environmental and health concerns. This study investigated the synthesis of zeolite NaA modified with Na2SO4 (Na2SO4@zeolite NaA) hydrothermal method and subsequent use as an adsorbent along with manganese dioxide (MnO2) for removing radium isotopes (226Ra and 228Ra) from acidic radioactive wastewater (ARW). ARW was generated through acidic sequential leaching of petroleum-based organic soils collected from the South Rumaila fields in the Basra Governorate, Iraq. The optimum adsorption parameters were MnO2: Na2SO4@zeolite NaA mass ratio of 1:0.5 g.g−1 and a pH of 6.3 resulting in maximum removal of 78.7% and 66.7% for 226Ra and 228Ra, respectively. Higher levels of removal were not attainable due to co-elements effect. The adsorption was endothermic with cation exchange of Na+ with Ra2+ being the main mechanism. The incorporation of Na2SO4 increased the exchange sites available for Ra2+ and the surface area and pore size available for facilitating such reactions. The exhausted column was regenerated and subsequently used for five cycles with a small drop in the removal of 226Ra and 228Ra by 11% and 9.5%, respectively highlighting the propitious application of Na2SO4@zeolite NaA and MnO for treating contaminated wastewater in oil fields.

Two Iterative Methods for Sizing Pipe Diameters in Gas Distribution Networks with Loops

Closed-loop pipe systems allow the possibility of the flow of gas from both directions across each route, ensuring supply continuity in the event of a failure at one point, but their main shortcoming is in the necessity to model them using iterative methods. Two iterative methods of determining the optimal pipe diameter in a gas distribution network with closed loops are described in this paper, offering the advantage of maintaining the gas velocity within specified technical limits, even during peak demand. They are based on the following: (1) a modified Hardy Cross method with the correction of the diameter in each iteration and (2) the node-loop method, which provides a new diameter directly in each iteration. The calculation of the optimal pipe diameter in such gas distribution networks relies on ensuring mass continuity at nodes, following the first Kirchhoff law, and concluding when the pressure drops in all the closed paths are algebraically balanced, adhering to the second Kirchhoff law for energy equilibrium. The presented optimisation is based on principles developed by Hardy Cross in the 1930s for the moment distribution analysis of statically indeterminate structures. The results are for steady-state conditions and for the highest possible estimated demand of gas, while the distributed gas is treated as a noncompressible fluid due to the relatively small drop in pressure in a typical network of pipes. There is no unique solution; instead, an infinite number of potential outcomes exist, alongside infinite combinations of pipe diameters for a given fixed flow pattern that can satisfy the first and second Kirchhoff laws in the given topology of the particular network at hand.

Slow evaporation of a small sessile liquid drop: new solutions based on the electrostatic analogy

Evaporating sessile drop of liquid deposited on horizontal surface is an important object of applications and theoretical investigations. The evaporating flow density dramatically depends on contact angle of the droplet. Previously, the dependence of the flux density on the polar angle was established for arbitrary contact angles. The expression has the form of an integral and is rather complicated for use in modelling algorithms. In this paper, we propose new exact solutions for the set of some specific contact angles (135-180 degrees). The analogy of the drop evaporation problem with a similar problem from the field of electrostatics of equipotential surfaces, which has been solved in general terms before us, was used. The results of British mathematician H.M. Macdonald and Soviet scientist G.A. Grinberg were used in the derivation. Thus, relatively simple expressions for the evaporation flux density were found.

Pull-out strength of screws in long bones at different insertion angles: finite element analysis and experimental investigations

Abstract Different types of plates are available to allow insertion of screws for internal fixation of long bone fractures. The aim of the study was to determine the effect of the insertion of screws at different angles on a long bone to the pull-out strength. Using 3D printed bone models, we tested the pull-out strength of screws in long bones at insertion angles between 0 and 40° with both finite element analysis and on printed models experimentally and compared the results. Test samples and cortical screws used were modeled with SolidWorks software and analyzed with Ansys software. As the screw insertion angle increases, the pull-out forces on the test specimens increase from 61.14 ± 3.5 N at 0° to 273 ± 6.8 N at 40° with an exception of a small drop between 15 and 20° from 235.4 ± 6.2 to 233 ± 6.9 N. Both methods showed an increase in the pull-out strength of screws as the insertion angle increases. This might be applicable in the clinical practice of bone fixation. Further studies on plate and screw fixation are needed to complement the findings.

Spermatozoa from male mice with infertility due to Odf4 deficiency can fertilize oocytes by invitro fertilization.

The purpose of this study is to confirm whether invitro fertilization (IVF) with spermatozoa from Odf4-deficient infertile males (Odf4 -/- spermatozoa) can lead to the development of zygotes, which was reported in a previous invivo study. In vitro capacitation and IVF were performed using Odf4 -/- spermatozoa in a small drop of TYH medium with pyruvate and glucose, for 60 min or up to 4 days. A capacitation test was performed by immunoblotting using an anti-p-Tyr antibody. A sperm movement test was performed using a computer-assisted sperm motility analysis system (SMAS). An IVF fertilization test was also performed to evaluate zygote production. Videos were taken by a DMi8 stereomicroscope equipped with a high-speed camera. In invitro condition, Odf4 -/- spermatozoa with hairpin flagella harboring large cytoplasmic droplets (CDs) underwent capacitation, about 30% of large CDs were removed from spermatozoa, and the flagella became straight (capacitation test). The Odf4 -/- spermatozoa with straight flagella swam forward (movement test) and fertilized Odf4 +/+ oocytes, which eventually developed into zygotes (fertilization test). By conventional IVF, spermatozoa from Odf4-deficient male mice can fertilize oocytes that then develop into zygotes. These findings can be translated to human males with infertility caused by ODF4 deficiency.

Investigation into contributions of fracture geometry characterization and interference to productivity of multi-fractured vertical gas well

Vertically fractured wells have been widely used to develop tight gas reservoirs. Characterizing the geometry of fractures created by hydraulic fracturing is a key factor influencing the productivity of such wells. Appropriately modeling the shapes of actual fractures is thus important for accurately predicting the well productivity. Past research in the area has tended to simplify fractures into straight lines, but this does not adequately represent the complex hydraulic fractures encountered in fractured reservoirs. In this study, we propose a generalized model for the productivity of a vertically fractured well to capture the characteristics of hydraulic fractures in gas fields. The proposed model accounts for several relevant mechanisms, including Knudsen slippage, characteristics of complex fracture geometry, and interference caused by multiple fractures. We validate the proposed model by applying it to a series of cases considered in the literature, and analytically examine key parameters such as the fracture number Nf and characteristics of the fracture geometry, including the length ratio a, width ratio b, branching angle θ and level n, fracture penetration ratio l0re, asymmetry in the length of fracture wing, and fracture intersection angle φ et al. The results show that there is a small drop in pressure between the inlet and outlet of the fracture. The well productivity is found to be positively associated with Nf, l0re, φ, and asymmetry in the length of the fracture wing. Furthermore, the productivity of a well intercepted by tree-shaped fractures primarily depends on a and n, and is almost entirely unaffected by b. By contrast, the well productivity gradually decreases with increasing θ. A tree-shaped fracture significantly enhances the well productivity by 110% (a=0.9, n=3), compared with a straight fracture. Finally, we provide an approach to increase the productivity of vertical wells based on the findings of this study.

Evaporation of Small Sessile Drop Deposited on a Horizontal Solid Surface: New Exact Solutions and Approximations

Evaporating a liquid sessile drop deposited on a horizontal surface is an important object of applications (printing technologies, electronics, sensorics, medical diagnostics, hydrophobic coatings, etc.) and theoretical investigations (microfluidics, self-assembly of nanoparticles, crystallization of solutes, etc.). The arsenal of formulas for calculating the slow evaporation of an axisymmetric drop of capillary dimensions deposited on a flat solid surface is reviewed. Characteristics such as vapor density, evaporation flux density, and total evaporation rate are considered. Exact solutions obtained in the framework of the Maxwellian model, in which the evaporation process of the drop is limited by vapor diffusion from the drop surface to the surrounding air, are presented. The summary covers both well-known results obtained during the last decades and new results published by us in the last few years, but practically unknown to the wider scientific community. The newest formulas, not yet published in refereed publications, concerning exact solutions for a number of specific contact angles are also presented. In addition, new approximate solutions are presented (total evaporation rate and mass loss per unit surface area per unit time in the whole range of contact angles θ∈[0, π), drop lifetime in constant contact radius evaporation regime and constant contact angle mode), which can be used in modeling without requiring significant computational resources.

Rural credit in Brazil: a survey of the state of the art

This study aims to map the state of the art of scientific publications on rural credit in Brazil. The focus is on identifying and understanding how the scientific literature has been addressing the topic in its different nuances - with public and private resources. Therefore, we performed a systematic review of the researched content to quantitatively and qualitatively identify the results. We conducted searches in the Web of Science, Scielo, Scopus, and Science Direct databases using the descriptors ("crédito rural") OR ("crédito agrícola") OR ("crédito agropecuário") and ("rural credit") OR ("agricultural credit"). The search included the application of a filter for the year of publication (between 2017 and 2022). Tabulation comprised StArt and Microsoft Excel tools. Out of the 170 articles selected for the bibliometric analysis, 11 were eligible to undergo content analysis. The results showed that the number of studies on the topic grew each year, with 2020 (35) having the highest number of investigations, followed by a small drop in 2021 (30). Furthermore, we identified an Authorship Network with five researchers coordinated by Professor Dr. Carlos José Caetano Bacha from the Graduate Program in Applied Economics of the "Luiz de Queiroz" School of Agriculture (ESALQ) at the University of São Paulo (USP) in Piracicaba/SP.