Pattern of Referral of Obstetric Patients at a Tertiary Care Hospital in Southern Nigeria

Background: Health challenges that are difficult to manage at primary health centres should be referred to secondary health facilities, and if untreated, to the tertiary hospitals. A good referral should include the patient’s biography, such as age, gender, tribe, religion, occupation, medical history, the reason for the referral, treatments received, and clinical diagnosis. Objectives: To evaluate the referral patterns, indications for referrals, and feto-maternal outcomes for obstetric patients who were referred to the University of Port Harcourt Teaching Hospital. Materials and Methods: A prospective study of patients admitted to the Obstetric unit from January 1, 2021, to December 31, 2022. Data was collected from patients while on admission or clinic visits and recorded in an excel spread sheet. Data was analyzed with the Statistical Package for Social Sciences (SPSS) version 25. Results: Of the 3469 patients were admitted to the obstetric unit, 1476 and 1993 were admitted in 2021 and 2022, respectively. Most (70.35%) of the patients were in the 20-34 years age group, parity 1-4 was the most frequent (66.49%), while 85.39% of patients were booked. 10.46% of the booked patients were referred from other facilities, whereas 89.54% of patients were booked at our facility from the onset. Most common indications of referrals were previous caesarean section (CS) at term (40.09%) and hypertensive disorders of pregnancy (17.59%). The outcome for 2021 indicated 17 maternal deaths, 132 fetal deaths and 1010 live births, giving maternal mortality ratio (MMR) as 1810.44 per 100,000 live births and perinatal mortality ratio (PMR) of 130.7 per 1000 births respectively. In 2022, there were 17 maternal deaths, 130 fetal deaths and 1297 deliveries, giving a MMR of 1399 per 100,000 live births and a PMR of 100.2 per 1000 births. Conclusion: The pattern of referral among obstetric patients in this study shows that a lot of the patients do not get adequate care at the lower cadre of the referral system, hence adequate facilities should be made available in primary and secondary health centres to tackle obstetric emergencies.

Application of CFD and FEA Coupling to Predict Structural Dynamic Responses of A Trimaran in Uni-and Bi-Directional Waves

To predict the wave loads of a flexible trimaran in different wave fields,a one-way interaction numerical simulation method is proposed by integrating the fluid solver(Star-CCM+)and structural solver(Abaqus).Differing from the existing coupled CFD-FEA method for monohull ships in head waves,the presented method equates the mass and stiffness of the whole ship to the hull shell so that any transverse and longitudinal section stress of the hull in oblique waves can be obtained.Firstly,verification study and sensitivity analysis are carried out by comparing the trimaran motions using different mesh sizes and time step schemes.Discussion on the wave elevation of uni-and bi-directional waves is also carried out.Then a comprehensive analysis on the structural responses of the trimaran in different uni-directional regular wave and bi-directional cross sea conditions is carried out,respectively.Finally,the differences in structural response characteristics of trimaran in different wave fields are studied.The results show that the present method can reduce the computational burden of the two-way fluid-structure interaction simulations.

A chaotic hierarchical encryption/watermark embedding scheme for multi-medical images based on row-column confusion and closed-loop bi-directional diffusion

Security during remote transmission has been an important concern for researchers in recent years.In this paper,a hierarchical encryption multi-image encryption scheme for people with different security levels is designed,and a multiimage encryption(MIE)algorithm with row and column confusion and closed-loop bi-directional diffusion is adopted in the paper.While ensuring secure communication of medical image information,people with different security levels have different levels of decryption keys,and differentiated visual effects can be obtained by using the strong sensitivity of chaotic keys.The highest security level can obtain decrypted images without watermarks,and at the same time,patient information and copyright attribution can be verified by obtaining watermark images.The experimental results show that the scheme is sufficiently secure as an MIE scheme with visualized differences and the encryption and decryption efficiency is significantly improved compared to other works.

Acceptability of Phone-Based Communication Intervention by Healthcare Workers as an Adjunct to Routine Referral Form: A Qualitative Study in South Western Uganda

Introduction: A functional maternal referral system should encompass a feasible communication system between health facilities. In Uganda, the current paper-based patient referral form is associated with inadequate patient-information and low feedback rates. A recent quasi-experimental study demonstrated that a phone-based communication intervention is feasible for iterative communication between health facilities, and there were improved maternal-fetal outcomes and high rates of feedback. However, the acceptability of the intervention was not assessed. Objective: The study assessed the acceptability of a phone-based communication intervention by the health care workers (HCWs) for iterative communication between the referring and receiving health facilities. Methods: This was a qualitative study conducted in South Western Uganda, in April 2021. The study employed a theoretical framework of acceptability of medical interventions. We conducted in-depth interviews with HCWs and used deductive-inductive analysis. Results: We enrolled a total of 23 HCWs, of whom 69.6% (n = 16) were females while 30.4% (n = 7) were males. Majority (65.2%, n = 15), were midwives and the rest were: doctors (30.4%, n = 7) and a nurse (4.3%). The HCWs were positive towards the intervention: they believed that the intervention reduced delays, promoted professional escort, encouraged sharing of supplies, enabled exchange of relatively more patient details, feedback and improved case management. They believed it was culturally acceptable and had enough skills and experience of operating phones. All participants recommended scale out of the intervention, but advised on the need for dedicated human-resource to coordinate phone calls, ensure availability of airtime and charged battery. Conclusion: This study demonstrates that the phone-based communication intervention was highly accepted by the healthcare workers, and that hospitals can successfully give feedback to lower health centres through iterative phone calls. This provides a possible solution to the long-standing challenge of poor feedback rates and a vicious cycle of poor maternal-fetal outcomes in resource limited settings.

Socio-Demographic Factors, Clinical Characteristics and Maternal Prognosis of Hypertensive Disorders in Pregnancy at Panzi General Referral Hospital

Background: Hypertensive disease in pregnancy is an important cause of morbidity, long-term disability, and maternal and neonatal mortality. The aim is to determine the socio-demographic characteristics and maternal prognosis of these women with Hypertension during pregnancy. Material and Method: We conducted a cross-sectional study, we interview patients and after discussion we transcripts in a database in Excel software before analysis with SPSS version 20.0 and Stata 14.0 The qualitative variables have been summarised by the Percentage and the quantitative variables will be summarised by Means and Standard Deviation. The associations of the variables were calculated by Pearson’s chi-square test with a significance level set at a p-value Result: The average age of the patients was 30.33 ± 7.020 years, 92.1% were married, 79.8% lived in urban areas, most of the patients were overweight (43%), 92.1% of them had monofetal pregnancies, 36% were multiparous, 34.2% had a previous history of preeclampsia in pregnancy and 14% were known to have hypertension. Pre-eclampsia was the most frequent form of hypertension in pregnancy with 73.68% of cases and represents 84.8% of severe forms of hypertension in pregnancy, 53.4% of the patients delivered vaginally. Eclampsia was the most frequent complication in our patients with 31.7% frequency and among the socio-demographic parameters, age and body mass index were significantly associated with maternal complications. Conclusion: Maternal age and body mass index are important socio-demographic factors associated with the occurrence of maternal complications in women with hypertensive disorders in pregnancy.

Text Sentiment Analysis Based on Multi-Layer Bi-Directional LSTM with a Trapezoidal Structure

Sentiment analysis,commonly called opinion mining or emotion artificial intelligence(AI),employs biometrics,computational linguistics,nat-ural language processing,and text analysis to systematically identify,extract,measure,and investigate affective states and subjective data.Sentiment analy-sis algorithms include emotion lexicon,traditional machine learning,and deep learning.In the text sentiment analysis algorithm based on a neural network,multi-layer Bi-directional long short-term memory(LSTM)is widely used,but the parameter amount of this model is too huge.Hence,this paper proposes a Bi-directional LSTM with a trapezoidal structure model.The design of the trapezoidal structure is derived from classic neural networks,such as LeNet-5 and AlexNet.These classic models have trapezoidal-like structures,and these structures have achieved success in the field of deep learning.There are two benefits to using the Bi-directional LSTM with a trapezoidal structure.One is that compared with the single-layer configuration,using the of the multi-layer structure can better extract the high-dimensional features of the text.Another is that using the trapezoidal structure can reduce the model’s parameters.This paper introduces the Bi-directional LSTM with a trapezoidal structure model in detail and uses Stanford sentiment treebank 2(STS-2)for experiments.It can be seen from the experimental results that the trapezoidal structure model and the normal structure model have similar performances.However,the trapezoidal structure model parameters are 35.75%less than the normal structure model.

A Modified Bi-Directional Evolutionary Structural Optimization Procedure with Variable Evolutionary Volume Ratio Applied to Multi-Objective Topology Optimization Problem

Natural frequency and dynamic stiffness under transient loading are two key performances for structural design related to automotive,aviation and construction industries.This article aims to tackle the multi-objective topological optimization problem considering dynamic stiffness and natural frequency using modified version of bi-directional evolutionary structural optimization(BESO).The conventional BESO is provided with constant evolutionary volume ratio(EVR),whereas low EVR greatly retards the optimization process and high EVR improperly removes the efficient elements.To address the issue,the modified BESO with variable EVR is introduced.To compromise the natural frequency and the dynamic stiffness,a weighting scheme of sensitivity numbers is employed to form the Pareto solution space.Several numerical examples demonstrate that the optimal solutions obtained from the modified BESO method have good agreement with those from the classic BESO method.Most importantly,the dynamic removal strategy with the variable EVR sharply springs up the optimization process.Therefore,it is concluded that the modified BESO method with variable EVR can solve structural design problems using multi-objective optimization.

Wave propagation responses of porous bi-directional functionally graded magneto-electro-elastic nanoshells via nonlocal strain gradient theory

This study examines the wave propagation characteristics for a bi-directional functional grading of barium titanate(BaTiO_(3)) and cobalt ferrite(CoFe_(2)O_(4)) porous nanoshells,the porosity distribution of which is simulated by the honeycomb-shaped symmetrical and asymmetrical distribution functions.The nonlocal strain gradient theory(NSGT) and first-order shear deformation theory are used to determine the size effect and shear deformation,respectively.Nonlocal governing equations are derived for the nanoshells by Hamilton's principle.The resulting dimensionless differential equations are solved by means of an analytical solution of the combined exponential function after dimensionless treatment.Finally,extensive parametric surveys are conducted to investigate the influence of diverse parameters,such as dimensionless scale parameters,radiusto-thickness ratios,bi-directional functionally graded(FG) indices,porosity coefficients,and dimensionless electromagnetic potentials on the wave propagation characteristics.Based on the analysis results,the effect of the dimensionless scale parameters on the dispersion relationship is found to be related to the ratio of the scale parameters.The wave propagation characteristics of nanoshells in the presence of a magnetoelectric field depend on the bi-directional FG indices.

Delayed referral for liver transplant evaluation worsens outcomes in chronic liver disease patients requiring inpatient transplant evaluation

BACKGROUND Indications to refer patients with cirrhosis for liver transplant evaluation(LTE)include hepatic decompensation or a model for end stage liver disease(MELDNa)score≥15.Few studies have evaluated how delaying referral beyond these criteria affects patient outcomes.AIM To evaluate clinical characteristics of patients undergoing inpatient LTE and to assess the effects of delayed LTE on patient outcomes(death,transplantation).METHODS This is a single center retrospective cohort study assessing all patients undergoing inpatient LTE(n=159)at a large quaternary care and liver transplant center between 10/23/2017-7/31/2021.Delayed referral was defined as having prior indication(decompensation,MELD-Na≥15)for LTE without referral.Early referral was defined as referrals made within 3 mo of having an indication based on practice guidelines.Logistic regression and Cox Hazard Regression were used to evaluate the relationship between delayed referral and patient outcomes.RESULTS Many patients who require expedited inpatient LTE had delayed referrals.Misconceptions regarding transplant candidacy were a leading cause of delayed referral.Ultimately,delayed referrals negatively affected overall patient outcome and an independent predictor of both death and not receiving a transplant.Delayed referral was associated with a 2.5 hazard risk of death.CONCLUSION Beyond initial access to an liver transplant(LT)center,delaying LTE increases risk of death and reduces risk of LT in patients with chronic liver disease.There is substantial opportunity to increase the percentage of patients undergoing LTE when first clinically indicated.It is crucial for providers to remain informed about the latest guidelines on liver transplant candidacy and the transplant referral process.

Frequency of and reasons behind non-listing in adult patients referred for liver transplantation: Results from a retrospective study

BACKGROUND Few studies have evaluated the frequency of and the reasons behind the refusal of listing liver transplantation candidates.AIM To assess the ineligibility rate for liver transplantation and its motivations.METHODS A single-center retrospective study was conducted on adult patients which entailed a formal multidisciplinary assessment for liver transplantation eligibility.The predictors for listing were evaluated using multivariable logistic regression.RESULTS In our center,314 patients underwent multidisciplinary work-up before liver transplantation enlisting over a three-year period.The most frequent reasons for transplant evaluation were decompensated cirrhosis(51.6%)and hepatocellular carcinoma(35.7%).The non-listing rate was 53.8%and the transplant rate was 34.4%for the whole cohort.Two hundred and five motivations for ineligibility were collected.The most common contraindications were psychological(9.3%),cardiovascular(6.8%),and surgical(5.9%).Inappropriate or premature referral accounted for 76(37.1%)cases.On multivariable analysis,a referral from another hospital(OR:2.113;95%CI:1.259–3.548)served as an independent predictor of non-listing.CONCLUSION A non-listing decision occurred in half of our cohort and was based on an inappropriate or premature referral in one case out of three.The referral from another hospital was taken as a strong predictor of non-listing.

Pilot Study of Molecular Mechanism on Vasculogenic Mimicry in Bi-directional Differentiated Malignant Tumors

Objective: To investigate the role of collagen IV and PAS positive substancesecreted by tumor cells in vasculogenic mimicry (VM) and the effects of VM on tumor cells expressingVEGF. Methods: 158 cases of bi-direction differential malignant tumor specimens withparaffin-embedded were enrolled into our study and made tissue microarray which were dual-stainedwith CD31-PAS and stained with collagen IV. The difference of the areas and distribution withpattern surrounded by between CD31 and PAS positive respectively were identified via grid-counting,as well as the difference of VEGF expression with VE absent and present. Results: The basementmembrane of VM was both PAS and collagen IV positive. VEGF expression in the bi-directiondifferential malignant tumor was higher VM-absent than VM-present and the difference wasstatistically significance in malignant melanoma and alveolar rhabdomyosarcoma (P 【 0.05).Conclusion: PAS positive substance and collagen IV compose the wall of VE and VE could provide theoxygen and nutrition for tumor growth and progression.

Description and Factors Affecting the Referral of Presumptive Tuberculosis Patients in China

To describe and analyze the factors affecting the referral of presumptive tuberculosis patients between health-care facilities that are not affiliated with the National TB Control Program （NTP） and NTP-designated medical facilities in China, we carried out a retrospective study based on data collected in the Tuberculosis Information Management System in 2015. Out of 324,221 presumptive pulmonary tuberculosis （PTB） cases reported by non-NTP health-care facilities, 302,006 （93.1%） reported cases successfully arrived at designated medical facilities and 22,215 cases （6.9%） were lost to follow-up. The arrival rate of presumptive cases among male patients （92.9%） was slightly lower than that among female ones （93.7%）, and this difference is statistically significant. The majority （73.3%） of reported cases were local permanent residents. Migrants have a higher risk of being lost to follow-up compared with local residents （adjusted odds ratios 4.126 and 5.003, respectively）. Compared with farmers and herdsmen, pre-school children, unemployed laborers, retirees, and people with other occupations （adjusted odds ratios 2.361, 1.274, 1.068, and 1.993, respectively） had higher rates of loss to follow-up during the referral and tracing processes. In conclusion, this study demonstrates that the high referral rate of presumptive TB cases from non-NTP health-care facilities to designated medical facilities in China is due to implementation of effective active case identification strategies. In addition, migrant populations, pre-school children, unemployed laborers, and retirees were identified as high-risk groups that contribute to the loss to follow-up.

Multi-agent system application in accordance with game theory in bi-directional coordination network model

The multi-agent system is the optimal solution to complex intelligent problems. In accordance with the game theory, the concept of loyalty is introduced to analyze the relationship between agents' individual income and global benefits and build the logical architecture of the multi-agent system. Besides, to verify the feasibility of the method, the cyclic neural network is optimized, the bi-directional coordination network is built as the training network for deep learning, and specific training scenes are simulated as the training background. After a certain number of training iterations, the model can learn simple strategies autonomously. Also,as the training time increases, the complexity of learning strategies rises gradually. Strategies such as obstacle avoidance, firepower distribution and collaborative cover are adopted to demonstrate the achievability of the model. The model is verified to be realizable by the examples of obstacle avoidance, fire distribution and cooperative cover. Under the same resource background, the model exhibits better convergence than other deep learning training networks, and it is not easy to fall into the local endless loop.Furthermore, the ability of the learning strategy is stronger than that of the training model based on rules, which is of great practical values.

Study on Application of Bi-directional Combination Technology Integrating Residue Hydrotreating with Catalytic Cracking RICP

After analysing the disadvantages of the traditional residue hydrotreating-catalytic cracking combination process, RIPP has proposed a bi-directional combination technology integrating residue hydrotreating with catalytic cracking called RICP which does not further recycles the FCC heavy cycle oil (HCO) inside the FCC unit and delivers HCO to the residue hydrotreating unit as a diluting oil for the residue that is concurrently subjected to hydrotreating prior to being used as the FCC feed oil. The RICP technology can stimulate residue hydrotreating reactions through utilization of HCO along with an in- creased yield of FCC light distillate, resulting in enhanced petroleum utilization and economic benefits of the refinery.

Experimental Investigation of Local Scour Around A New Pile-Group Foundation for Offshore Wind Turbines in Bi-Directional Current

The local scour around a new pile-group foundation of offshore wind turbine subjected to a bi-directional current was physically modeled with a bi-directional flow flume. In a series of experiments, the flow velocity and topography of the seabed were measured based on a system composed of plane positioning equipment and an ADV.Experimental results indicate that the development of the scour hole was fast at the beginning, but then the scour rate decreased until reaching equilibrium. Erosion would occur around each pile of the foundation. In most cases, the scour pits were connected in pairs and the outside widths of the scour holes were larger than the inner widths. The maximum scour depth occurred at the side pile of the foundation for each test. In addition, a preliminary investigation shows that the larger the flow velocity, the larger the scour hole dimensions but the shorter equilibrium time. The field maximum scour depth around the foundation was obtained based on the physical experiments with the geometric length scales of 1:27.0, 1:42.5 and 1:68.0, and it agrees with the scour depth estimated by the HEC-18 equation.

Construction and analysis of a plant transformation binary vector pBDGG harboring a bi-directional promoter fusing dual visible reporter genes

The constitutive promoter of cauliflower mosaic virus 35S （CaMV 35S） is a polar unidirectional promoter and is widely used in plant genetic engineering. In the present study, the unidirectional CaMV 35S promoter has been modified to a bi-directional promoter by fusing its minimal promoter element to the 5＇ end of CaMV 35S promoter in the opposite orientation. To qualitatively and quantitatively estimate its bi-directional transcriptional function and activity, two visible reporter genes, gusA （13-glucuronidase, GUS） and gfp （green fluorescent protein, GFP）, were fused to the two ends of the promoter in bi-orientations ending with NOS terminator sequences, respectively. Stable expression of gusA and gfp genes in transgenic tobacco （Nicotiana tabacum L.） was visulized by histochemically staining for GUS and fluorescence microscopic observation under UV for GFP in transgenic plants. The expression of two reporter genes showed that the constructed bi-directional promoter did have the bi-directional transcriptional function in both expected orientations. The quantitative estimation of GUS and GFP were determined on a HITACHI F1000 Fluorescence Spectrophotometer with various wavelengths of excitation and emission. The GUS activity varied from g to 250 pmol 4-MU/min/mg protein and the GFP content varied from 0.9 to 1.8 μg/ mg protein in various lines of transgenic tobacco plants. Higher GUS activity generally coupled with lower GFP content, and vice versa.

A High-Speed Bi-Directional Visible Light Communication System Based on RGB-LED

In this paper, we propose and experimentally demonstrate a bi-directional indoor communication system based on visible light RGB-LED. Spectrally efficient modulation formats （QAM-OFDM）, advanced digital signal processing, pre- and post- equalization are adopted to compensate the severe frequency response of indoor channel. In this system, we utilize red-green-blue Light emitting diodes （LEDs）, of which each color can be used to carry different signals. For downlink, the low frequencies of each color are used while for uplink, the high frequencies are used. The overall data rate of downlink and uplink are 1.15-Gb/s and 300-Mb/s. The bit error ratios （BERs） for all channels after 0.7 m indoor delivery are below pre-forward- error-correction （pre-FEC） threshold of 3.8×10-3. To the best of our knowledge, this is the highest data rate in bi-directional visible light communication system.

Quantitative measurements of one-dimensional OH absolute concentration profiles in a methane/air flat flame by bi-directional laser-induced fluorescence

The one-dimensional （1D） spatial distributions of OH absolute concentration in methane/air laminar premixed flat flame under different equivalence ratios at atmospheric pressure are investigated by using bi-directional laser-induced flu- orescence （LIF） detection scheme combined with the direct absorption spectroscopy. The effective peak absorption cross section and the average temperature at a height of 2 mm above the burner are obtained by exciting absorption on the Q1（8） rotational line in the A2∑＋ （Dt = 0） ←- X2∏ （v = 0） at 309.240 nm. The measured values are 1.86×10-15 cm2 and 1719 K, respectively. Spatial filtering and frequency filtering methods of reducing noise are used to deal with the experi- mental data, and the smoothing effects are also compared using the two methods. The spatial distribution regularities of OH concentration are obtained with the equivalence ratios ranging from 0.8 to 1.3. The spatial resolution of the measured result is 84μm. Finally, a comparison is made between the experimental result of this paper and other relevant study results.

Application of bi-directional static loading test to deep foundations

Bi-directional static loading test adopting load cells is widely used around the world at present, with increase in diameter and length of deep foundations. In this paper, a new simple conversion method to predict the equivalent pile head load-settlement curve considering elastic shortening of deep foundation was put forward according to the load transfer mechanism. The proposed conversion method was applied to root caisson foundation in a bridge and to large diameter pipe piles in a sea wind power plant. Some new load cells, test procedure, and construction technology were adopted based on the applications to different deep foundations, which could enlarge the application scopes of bi-directional loading test. A new type of bi-directional loading test for pipe pile was conducted, in which the load cell was installed and loaded after the pipe pile with special connector has been set up. Unlike the conventional bi-directional loading test, the load cell can be reused and shows an evident economic benefit.

Bending and free vibrational analysis of bi-directional functionally graded beams with circular cross-section

The bending and free vibrational behaviors of functionally graded(FG)cylindrical beams with radially and axially varying material inhomogeneities are investigated.Based on a high-order cylindrical beam model,where the shear deformation and rotary inertia are both considered,the two coupled governing differential motion equations for the deflection and rotation are established.The analytical bending solutions for various boundary conditions are derived.In the vibrational analysis of FG cylindrical beams,the two governing equations are firstly changed to a single equation by means of an auxiliary function,and then the vibration mode is expanded into shifted Chebyshev polynomials.Numerical examples are given to investigate the effects of the material gradient indices on the deflections,the stress distributions,and the eigenfrequencies of the cylindrical beams,respectively.By comparing the obtained numerical results with those obtained by the three-dimensional(3D)elasticity theory and the Timoshenko beam theory,the effectiveness of the present approach is verified.