bluuebunny/crossref_metadata_2025 huggingface dataset:
10kV+ Rated SiC n-IGBTs: Novel Collector-Side Design Approach Breaking the Trade-Off between dV/dt and Device Efficiency
Authors: Almpanis Ioannis , Evans Paul , Antoniou Marina , Gammon Peter Michael , Empringham Lee , Udrea Florin , Mawby Philip  Andrew , Lophithis Neophytos
Published: May 2023

10kV+ rated 4H- Silicon Carbide (SiC) Insulated Gate Bipolar Transistors (IGBTs) have the potential to become the devices of choice in future Medium Voltage (MV) and High Voltage (HV) power converters. However, one significant performance concern of SiC IGBTs is the extremely fast collector voltage rise (dV/dt) observed during inductive turn-off. Studies on the physical mechanisms of high dV/dt in 4H-SiC IGBTs revealed the importance of collector-side design in controlling the phenomenon. In this paper we propose a novel collector-side design approach, which consists of four n-type layers with optimized doping densities and allows the control of dV/dt independently from the device performance. Further, we demonstrate a reduction of dV/dt by 87% without degrading the high switching frequency capability of the device, or the on-state performance, through the addition of two n-type epitaxial layers in the collector side, between the buffer and the drift regions.
High-Speed Plasma Etching of Gallium Oxide Substrates Using Atmospheric-Pressure Plasma with Hydrogen-Helium Mixed Gas
Authors: Sano Yasuhisa , Sai Taiki , Nakaue Genta , Toh Daisetsu , Yamauchi Kazuto
Published: May 2023

In addition to silicon carbide (SiC) and gallium nitride (GaN), gallium oxide (Ga2O3) is attracting attention as a widegap semiconductor material. Ga2O3, unlike SiC and GaN, is not as hard, but has strong cleavage properties, making highly effective mechanical machining difficult. Thus, the processing of Ga2O3 by high-speed etching employing atmospheric-pressure plasma was studied. An extremely high removal rate of 60 μm/min was obtained due to basic processing experiments using hydrogen gas instead of toxic and corrosive chlorine gas as the reaction gas.
Design and Implementation of Montmorillonite Clay-Based Catalyst for Carbon Nanotube Synthesizing
Authors: Morsy Mohamed , Shoukry Hamada , Garieb Mahmoud , El-Nagar Abdeen , Taha Walaa M. , Mokhtar Mahmoud M.
Published: May 2023

In this study, a catalyst based on Montmorillonite clay was implemented for carbon nanotubes (CNTs) synthesizing. The kaolinite clay was used as a supporting material for iron-cobalt bimetallic catalytic nanoparticles. The CNTs have been synthesized by using atmospheric chemical vapor deposition (APCVD). To assess the quality of preparation both the catalyst and CNTs have been characterized by different techniques. The chemical bonding and interactions were verified by FT-IR. The general overview of microstructure was examined using SEM, while, the detailed structure and morphology were examined by HR-TEM, in addition to thermal analysis (DTA); surface area (BET); X-ray fluorescence (XRF), Raman spectroscopy, and XRD analysis. The results revealed that; Fe2O3 and Co3O4 NPs were uniformly assembled on the clay nanoplatelets. The specific BET surface area of the clay and catalyst was determined to be 46.12 and 57.06 m2/g respectively. Also, from XRD, the peaks at 26° and 42.7° confirm the presence of CNTs. The FTIR absorption bands, D, G, and G\ bands from the Raman spectrum confirm the hexagonal structure of the CNTs. The obtained results prove the high quality of CNTs preparation.
Improving the Polishing Speed and Surface Quality of 4H-SiC Wafers with an MnO2- Based Slurry
Authors: Nakamura Takuma , Kumagai Akinori , Saruwatari Yasunobu , Hara Shuhei
Published: May 2023

We carried out chemical mechanical polishing (CMP) on commercially available 6 inch SiC wafers (epi-ready products) with slurries containing different abrasive types and evaluated the latent scratch density from the mapping measurement of the wafers using mirror projection electron microscope (MPJ). Comparing to the wafer before polishing, the latent scratch density decreased on the wafer polished with MnO2+KMnO4, while that increased by polishing with Al2O3+KMnO4. The two-step polishing using first Al2O3+KMnO4 and then SiO2+H2O2 can reduce the latent scratch density to the same level as that with MnO2+KMnO4, but long polishing time is required because of the low polishing rate in the process with SiO2+H2O2. We investigated the reason why MnO2 slurry can suppress the occurrence of latent scratches by a polishing test on a wafer with an SiO2 film on its (0001)Si surface. The results suggest the oxidation of the SiC surface is rate-determining step for polishing with MnO2+KMnO4. It was also found that wafers without an SiO2 film could not be polished with only MnO2 abrasives. Thus the mechanical contribution to polishing by MnO2 abrasives in KMnO4-based slurry is smaller than the chemical contribution, which can suppress the occurrence of latent scratches. KMnO4-based slurry containing MnO2 abrasives performs the CMP process with low latent scratch density in a time shorter than that containing Al2O3 or SiO2 abrasives.
Effect of Melting Temperature and Flux on Slag Percentage in Die Casting Process of Zamak3 Alloy
Authors: Inpunyo Chawalit , Kongphan Phanphong , Torsakul Sirichai , Waewdee Suthiwat , Laohavanich Adisorn , Wirot Pun , Vaodee Somkuan
Published: May 2023

This research aims to identify the optimal condition of the zinc Zamak3 alloys' melting process using 2k full factorial design and its optimizer in Minitab 18 software. The evaluation results of the ANOVA test with a first-order model revealed that the change in both independent variables simultaneously resulted in a statistically significant alteration of the percentage of slag. The independent parameters also had an effect individually on the response. Additionally, the slag percentage reduction was increased significantly due to an elevation of the temperature. However, the change of flux type resulted in an overall alteration of the slag percentage more than the change of melting temperature. The response optimizer demonstrated that the optimal condition was the melting temperature of 500°C coupled with the ZinCrex EP7119 flux achieving the lowest slag percentage of 1.672%, with the 95% confidence interval ranging from 0.643% to 2.701%.
Influence of Tool Eccentricity pin Positioning on AA6061 Aluminium Alloy Friction Stir Welds
Authors: Ahmad Shah Luqman Hakim , Ramachandiran Nivas , Hou Wen Tao , Gerlich Adrian
Published: May 2023

This study examines the influence of tool eccentricity pin positioning on AA6061 aluminium alloy friction stir welds. A laser scanning confocal microscope and optical microscope was used to analyze the surface roughness and the cross-sectional microstructure of the samples. Surface roughness analysis reveal the thread-to-flat (T2F) samples show rougher surface with increasing rotational speed up to 1400 rpm. On the other hand, the surface appearance of flat-to-thread (F2T) samples show minimal change. Cross-sectional microstructural observations show that the stir zone area of both groups increases with increasing rotational speed. However, the periodic bands in T2F and F2T samples increases in the upper region and lower region of the stir zone, respectively.
Impacts of Wafer Doping Type on Structural and Optical Properties of Black Silicon Fabricated by Metal-Assisted Chemical Etching
Authors: Sheriff Muhiddin Ahmad , Abdulkadir Auwal , Hashim Md. Roslan , Pakhuruddin Mohd Zamir
Published: May 2023

In this work, the impacts of wafer doping type on structural and optical properties of black silicon (b-Si) fabricated by metal-assisted chemical etching (MACE) process are investigated. P-type and n-type mono-crystalline silicon (mono c-Si) wafers are etched in an aqueous solution of hydrofluoric acid (HF), silver nitrate (AgNO3) and deionised water (DI H2O) at room temperature and various durations from 5-20 minutes. Surface morphological results demonstrate the formation of b-Si nanowires (NWs) with average lengths of 0.4-0.8 μm for p-type wafers and 0.8-3.0 μm for n-type wafers. The higher length of the NWs for the n-type wafers is due to the minority charge carriers, which lead to a higher etching rate during the MACE process. Within the 300-1100 nm wavelength region, weighted average reflection (WAR) for the p-type and n-type wafers decreases to 6.6% and 6.4%, respectively, after 20 minutes of etching. The corresponding improvement in broadband light absorption results in maximum potential short-circuit current density (Jsc (max)) of 38.2 and 38.8 mA/cm2 for the p-type and n-type b-Si, respectively, which is an of enhancement of 39.9% and 42.1% when compared to the Jsc (max) of planar c-Si reference.
Management of a road major trauma in a spoke hospital: a report of opioid-free anesthesia in a minimally invasive orthopedic surgery
Authors: Golino Ludovica , Saracco Michela , Caiazzo Marco , Russo Gianmarco , Fusco Fabrizio , Imperatore Francesco
Published: May 2023

Major trauma is bound to be managed in highly specialized centers. Due to logistics needs or due to an initial clinical stabilization, these patients happen to be managed in hospitals that are not fully equipped for trauma. We handled a patient, major trauma to dynamics following a high-speed collision between two cars in which she was behind the wheel. The patient was also complex due to cardiovascular and respiratory comorbidities. After ‘ABCDE’ and radiological evaluation, the patient was managed in our hospital with ICU recovery and multiple orthopedic interventions to which she was subjected with neuraxial and peripheral regional anesthesia. The patient was managed successfully and with excellent pain control. The risks associated with her comorbidities were limited to a minimum and she was discharged for rehabilitation 5 days after the operations.
Investigating local variation in disease rates within high-rate regions identified using smoothing
Authors: Tuson Matthew , Yap Matthew , Whyatt David
Published: May 2023

Exploratory disease maps are designed to identify risk factors of disease and guide appropriate responses to disease and helpseeking behaviour. However, when produced using aggregatelevel administrative units, as is standard practice, disease maps may mislead users due to the Modifiable Areal Unit Problem (MAUP). Smoothed maps of fine-resolution data mitigate the MAUP but may still obscure spatial patterns and features. To investigate these issues, we mapped rates of Mental Health- Related Emergency Department (MHED) presentations in Perth, Western Australia, in 2018/19 using Australian Bureau of Statistics (ABS) Statistical Areas Level 2 (SA2) boundaries and a recent spatial smoothing technique: the Overlay Aggregation Method (OAM). Then, we investigated local variation in rates within high-rate regions delineated using both approaches. The SA2- and OAM-based maps identified two and five high-rate regions, respectively, with the latter not conforming to SA2 boundaries. Meanwhile, both sets of high-rate regions were found to comprise a select number of localised areas with exceptionally high rates. These results demonstrate how, due to the MAUP, disease maps that are produced using aggregate-level administrative units are unreliable as a basis for delineating geographic regions of interest for targeted interventions. Instead, reliance on such maps to guide responses may compromise the efficient and equitable delivery of healthcare. Detailed investigation of local variation in rates within high-rate regions identified using both administrative units and smoothing is required to improve hypothesis generation and the design of healthcare responses.
Spatial analysis of the relationship between out-of-pocket expenditure and socioeconomic status in South Korea
Authors: Kwon Young-Gyu , Choi Man-Kyu
Published: May 2023

The rapid increase in out-of-pocket expenditures regressively raises the issue of equity in medical access opportunities according to income class and negatively affects public health. Factors related to out-of-pocket expenses have been analyzed in previous studies using an ordinary regression model (Ordinary Least Squares [OLS]). However, as OLS assumes equal error variance, it does not consider spatial variation due to spatial heterogeneity and dependence. Accordingly, this study presents a spatial analysis of outpatient out-of-pocket expenses from 2015 to 2020, targeting 237 local governments nationwide, excluding islands and island regions. R (version 4.1.1) was used for statistical analysis, and QGIS (version 3.10.9), GWR4 (version 4.0.9), and Geoda (version 1.20.0.10) were used for the spatial analysis. As a result, in OLS, it was found that the aging rate and number of general hospitals, clinics, public health centers, and beds had a positive (+) significant effect on outpatient out-of-pocket expenses. The Geographically Weighted Regression (GWR) suggests regional differences exist concerning out-of-pocket payments. As a result of comparing the OLS and GWR models through the Adj. R² and Akaike’s Information Criterion indices, the GWR model showed a higher fit. This study provides public health professionals and policymakers with insights that could inform effective regional strategies for appropriate out-of-pocket cost management.
Dynamic effect of economic growth on the persistence of suicide rates
Authors: Yang Tzu-Yi , Yang Yu-Tai , Chen Ssu-Han , Lan Yu-Ting , Peng Chia-Jui
Published: May 2023

Positive and negative economic growth is closely related to the suicide rate. To answer the question whether economic development has a dynamic impact on this rate, we used a panel smooth transition autoregressive model to evaluate the threshold effect of economic growth rate on the persistence of suicide. The research period was from 1994 to 2020, and the results show that the suicide rate had a persistent effect, which varied over time depending on the transition variable within different threshold intervals. However, the persistent effect was manifested in different degrees with the change in the economic growth rate and as the lag period of the suicide rate increased, the effect of the influence gradually decreased. We investigated different lag periods and noted that the impact on the suicide rate was the strongest in the first year after an economic change and then reduced to be only marginal after three years. This means that the growth momentum of the suicide rate within the first two years after a change in the economic growth rate, should be included in policy considerations of how to prevent suicides.
Spatial pattern and heterogeneity of chronic respiratory diseases and relationship to socio-demographic factors in Thailand in the period 2016 to 2019
Authors: Htwe Zar Chi , Laohasiriwong Wongsa , Sornlorm Kittipong , Mahato Roshan
Published: May 2023

Chronic respiratory diseases (CRDs) constitute 4% of the global disease burden and cause 4 million deaths annually. This cross-sectional study used QGIS and GeoDa to explore the spatial pattern and heterogeneity of CRDs morbidity and spatial autocorrelation between socio-demographic factors and CRDs in Thailand from 2016 to 2019. We found an annual, positive, spatial autocorrelation (Moran’s I >0.66, p<0.001) showing a strong clustered distribution. The local indicators of spatial association (LISA) identified hotspots mostly in the northern region, while coldspots were mostly seen in the central and north-eastern regions throughout the study period. Of the socio-demographic factors, the density of population, households, vehicles, factories and agricultural areas, correlated with the CRD morbidity rate, with statistically significant negative spatial autocorrelations and coldspots in the north-eastern and central areas (except for agricultural land) and two hotspots between farm household density and CRD in the southern region in 2019. This study identified vulnerable provinces with high risk of CRDs and can guide prioritization of resource allocation and provide target interventions for policy makers.
Prehistoric human migrations: a prospective subject for modelling using geographical information systems
Authors: Bergquist Robert
Published: May 2023

Researchers in many fields have discovered the advantage of using geographical information systems (GIS), spatial statistics and computer modelling, but these techniques are only sparingly applied in archaeological research. Writing 30 years ago, Castleford (1992) noted the considerable potential of GIS, but he also felt that its then atemporal structure was a serious flaw. It is clear that the study of dynamic processes suffers if past events cannot be linked to each other, or to the present, but today’s powerful tools have overcome this drawback. Importantly, with location and time as key indices, hypotheses about early human population dynamics can be tested and visualized in ways that can potentially reveal hidden relationships and patterns. [...]
Knowledge, attitude, intention, and program implementation of iron supplementation among adolescent girls in Sidoarjo, Indonesia
Authors: Hasianna Silitonga Hanna T. , Salim Lutfi A. , Nurmala Ira , Hargono Rachmat , Purwandini Septiana
Published: May 2023

Background: The government established an iron supplementation program as a solution to overcome anemia in adolescent girls in Indonesia. Research shows that various factors influence the compliance of adolescent girls in consuming iron supplements, including knowledge, attitude, intention, and program implementation. Objective: This study aims to determine adolescent girls’ knowledge, attitudes, and intentions and explore the program implementation of iron supplementation in high school adolescent girls in Sidoarjo, Indonesia.Materials and Methods: This was mixed-method research. Quantitative data was collected on 202 girls students from 3 high schools in Sidoarjo using a questionnaire.Qualitative data was collected by interviewing 13 high school girls from 3 schools in Sidoarjo and Focus Group Discussion with the health office and primary health center representatives in Sidoarjo.Results: Most adolescent girls’ knowledge about anemia was still poor (59.9%), but knowledge about iron supplements was mostly good (59.9%). The attitudes towards anemia and iron supplements and intentions to consume iron supplements in adolescent girls were mostly low (51.0% and 51.5%). The focus group discussion found that the program was already referred to national guidelines, but the pandemic affected the implementation. Findings from the interview with adolescent girls show that the distribution of iron supplements in schools was carried out in 3 ways: distributed with explanations, distributed without explanation, and distributed only to students who request it or feel anemic.Conclusion: There is a need to improve the knowledge, attitudes, and intentions of adolescent girls and improve the implementation of iron supplementation programs in schools in Sidoarjo, Indonesia.
The presence of microplastics in the Indonesian environment and its effects on health
Authors: Mulyasari Tri M. , Mukono Jojok , Sincihu Yudhiakuari
Published: May 2023

Introduction: Microplastics are plastic particles with a microscopic size of 5 mm in diameter. Microplastics are new contamination of the environment and can be bad for health.Objective: This paper aims to examine the presence of microplastics in the Indonesian environment based on the results of research in 2022 and its effects on health. Materials and Methods: Systematic review based on the results of research journals published in 2022. Journal obtained from a search on Google Scholar with keywords “microplastics”, “microplastics in Indonesia”, and “effect microplastic to health”. Results: The results of a review showed that the research location was dominated in East Jawa. The presence of microplastics in the environment in Indonesia is most widely studied, namely in river and sea sediments. The forms of microplastics identified are fiber, fragment, film, pellets, granule, foam, filament, and bead. In microplastic research on the environment in Indonesia in 2022, as much as 16% analyzed plastic polymer types. The study that identified the number, shape, and color of microplastics using visual methods with a microscope was 84%. Research on the effects of microplastics on health is still little done. Conclusions: Microplastics are widely studied in sediments, water, food, and air. Microplastics in the environment in Indonesia have been identified in number, shape, color, and polymer type. There have not been many studies that have conducted an analysis of the type of polymer. The environment in Indonesia has been polluted by microplastics that can have an impact on health.
Effectiveness of indoor and outdoor larvitrap modified jars and paralon hit for Aedes spp. control
Authors: Widyanto Arif , Unggul Satoto Tri B. , Kusmintarsih Endang S.
Published: May 2023

Background: Dengue hemorrhagic fever (DHF) is a disease caused by the dengue virus which is transmitted by the mosquito vector Aedes spp. Efforts to control dengue vectors using chemical methods such as the use of larvicides and fogging with insecticides can result in the risk of environmental pollution and also resistance to Aedes spp.Objective: This study aimed to analyze the effectiveness of indoor and outdoor modified larvitrap made from jars and black paralon as well as attractants to control Aedes spp.Methods: This research is applied research in society. Indoor and outdoor larvitrap is made using clear jars and black paralon. The attractants used were Imperata cylindrica soaking water, rice straw, and sugarcane leaves with concentrations of 20 and 30%. Indoor and outdoor larvitrap was installed in the respondent's house in a dengue-endemic area in Pandak village, Banyumas, Indonesia. Observations were carried out on the number of Aedes spp. larvae trapped by larvitrap. Results: The results showed that outdoor larvitraps caught fewer Aedes spp. larvae (46.8%) than indoor larvitraps (61.6%). The use of attractants between Imperata, rice straw, and sugarcane leaves has a different effect on the number of larvae caught. Most of the Aedes spp. larvae were caught in Imperata soaking water with a concentration of 30% installed in an indoor larvitrap. Conclusion: The use of indoor and outdoor larvitrap modified jars and black paralon at research sites can be effective for controlling Aedes spp. Imperata soaking water with a concentration of 30% proved to be the most effective attractant.
Histological evaluation of ProRoot mineral trioxide aggregate and Cold ceramic as root-end filling materials in animal models
Authors: Modaresi Jalil , Khademi Abbasali , Hemati Hamidreza , Mokhtari Fatemeh
Published: May 2023

Background:

This study aimed to evaluate the reaction of the periapical tissue to Cold ceramic and mineral trioxide aggregate (MTA) following periapical endodontic surgery.

Materials and Methods:

In this experimental study, a total of 12 mandibular first, second, and third premolars of two male dogs were selected. All procedures were performed under general anesthesia. The access cavities were prepared, and the length of canals was determined. Root canal treatment was performed. A week later, periradicular surgery was performed. After osteotomy, 3 mm of the root end was cut. Then, a 3-mm cavity was created by an ultrasonic. The teeth were randomly divided into two groups (n = 12). The root-end cavities were filled with MTA in the first group and with Cold ceramic in the second group. After 4 months, the animals were scarified. Histological evaluation of the periapical tissues was performed. Data were analyzed using SPSS 22 and Chi-square test and P = 0.05.

Results:

The findings showed 87.5% and 58.3% cementum formation in MTA and Cold ceramic groups, respectively, indicating a significant difference (P < 0.001). In addition, the results showed 91.7% and 83.3% bone formation in MTA and Cold ceramic groups, respectively, but the difference was not statistically significant (P = 0.6). Furthermore, the findings revealed 87.5% and 58.3% periodontal ligament (PDL) formation in MTA and Cold ceramic groups, respectively (P = 0.05).

Conclusion:

Cold ceramic was able to induce the regeneration of cementum, bone, and PDL; hence, it can be considered as a biocompatible root-end filling material in endodontic surgery.
Investigation of the effect of fibrin glue as a sealant in the unilateral alveolar bone grafting successes
Authors: Attar Bijan Movahedian , Naeini Mohammad Hossein Manouchehri , Abdinian Mehrdad
Published: May 2023

Background:

Bone grafting is the primary treatment for the alveolar cleft. Due to the reduced complications by the sealant materials, this study aimed to evaluate fibrin glue's effect on the success rate of unilateral alveolar bone grafting.

Materials and Methods:

This study was a single-blind clinical trial performed on 20 patients with a unilateral alveolar cleft. Patients were randomly divided into groups: group A patients as a control group underwent bone grafting without fibrin glue, and in Group B, patients were grafted using fibrin glue. The subject was followed up through routine examination and the cone-beam computed tomography systems technique for up to 4 months. Paired t-test and Chi-square tests were used to analyze the data and the P < 0.05 was considered the significance threshold.

Results:

The mean age, gender, and cleft side distribution did not represent significant differences. Before surgery, the average alveolar cleft volume in Group A and B patients was 0.95 ± 0.25 cm3 and 0.99 ± 0.22 cm3, respectively, which was not statistically different. After the surgery procedure, the alveolar cleft volume in Group A and B patients was determined to be 0.31 ± 0.10 cm3 and 0.23 ± 0.11 cm3, which represented 66.7% ± 8.9% cm3 and 76.2 ± 11.4 cm3 bone formation, respectively, with no remarkable difference. Our examination did not reveal any necrosis and infection in both groups. However, despite no dehiscence observation in fibrin glue treatment patients, one subject showed dehiscence complication in the control group.

Conclusion:

According to results, fibrin glue may increase the percentage of bone volume formed and prevent dehiscence.
Investigation of the effect of hydrochloric acid with different concentrations on mineral trioxide aggregate plug and dentin
Authors: Gharechahi Maryam , Moradi Saeed , Nasirnia Sina , Peighoun Maryam
Published: May 2023

Background:

Mineral trioxide aggregate (MTA) becomes a hard mass after setting and making it difficult to remove and can cause significant problems in the retreatment process. The aim of this study was to evaluate the effect of different concentrations of hydrochloric acid (HCl) on MTA dissolution and its effect on dentin.

Materials and Methods:

In this in vitro study, 45 single-root premolars were selected. Artificially open apex was created in all samples with similar process. The samples were randomly divided into 4 experimental groups of 10, and a control group of 5. Four-millimeter thick apical plugs of Root MTA were placed in all samples in an orthograde manner. HCl was used at concentrations of 3.75%, 7.5%, 15%, and 22.5% (w/v) for the experimental groups and normal saline for the control group. Each sample was exposed to the desired solution for 15 min. Then, MTA retrieval and reaching the working length were attempted with k-file # 30. The times of each sample were recorded. Furthermore, after longitudinal incision of the roots with a disc, the dentin surfaces of canals were examined with a Dino-Lite microscope (×50). Results were analyzed by Shapiro–Wilk test and one-way analysis of variance tests. The level of significance P value was set at 0.05.

Results:

The lowest average time of reaching working length was observed with group 22.5% that was significantly lower than 15% and 7.5% concentrations (P = 0.005 and P = 0.011). Furthermore, by examining with ×50 of Dino-Lite microscope, no difference was observed on the canal walls.

Conclusion:

The optimum concentration of HCl was 7.5%. Furthermore, different concentrations of HCl had no significantly different effect on the dentinal canal wall using Dino-Lite microscope with ×50.
Large distal tear of aortic dissection
Authors: Lv Lizhi , Chen Yanqing , Shen Yu , Jing Zaiping , Shi Yi , Zhang Simeng , Lu Qingsheng
Published: May 2023

BACKGROUND:

The traditional treatment for aortic dissections (ADs) is a proximal repair of AD, but the long-term prognosis of residual distal dissection is unsatisfactory. The distal aortic intimal tear of distal aortic segmental enlargement (DASE) is evaluated via its size, with risk assessment, and assessed its risk, which will provide clinicians with diagnosis and treatment direction.

METHODS:

We analyzed 419 ADs patients who underwent radiographic examination of the aorta between September 1999 and May 2014. We recorded the area of the aortic intimal tear and divided it into two groups (75 patients in DASE group and 344 patients in non-DASE group). Logistics regression analysis or natural logarithm transformation was used to explore the potential risk of remaining distal tears to DASE, while the Logistic multiple regress equations were used to find out the independent risk factors.

RESULTS:

The postoperative large tear was defined as short diameter ≥5.0 mm. The independent risk factors of DASE are as follows: Short diameter of postoperative tears (odds ratios [ORs], 1.10;95% confidence interval [CI], 1.02–1.19; P < 0.0120); short diameter of the first tear after operation (OR, 1.12; 95% CI, 1.00–1.26; P < 0.0580) and the existence of large tears (OR, 1.13; 95% CI, 1.01–1.26; P < 0.0298).

CONCLUSIONS:

Our findings suggest that the size of the remaining tears and the existence of large tears are the key risk factors for patients with DASE. Patients with large remaining tears should be supervised regularly and treated timely.
Open surgical repair of common femoral artery aneurysm
Authors: Kwan Kristine J. S. , Li Hai-Lei , Chan Yiu Che , Cui Dong-Zhe , Cheng Stephen W.
Published: May 2023

Common femoral artery (CFA) aneurysms are rare with an unknown exact incidence and often found in elderly males with chronic diseases. Early recommendations are to repair aneurysms with a maximum diameter of ≥2.5cm. We present the case of a 37-year-old male with a right CFA aneurysm. Open surgical repair (OSR) consisting of aneurysmectomy and reconstruction of the femoral artery with a bifurcated prosthetic graft was applied. Our study details this case and thoroughly reviews on the treatment of femoral artery aneurysms in the literature. OSR and vascular reconstruction with interposition prosthetic graft were durable and associated with favorable outcomes.
A Prospective, Randomized, Interventional, Comparative Study between Dexmedetomidine and Propofol Infusion for Monitored Anesthesia Care during Internal Jugular Vein Chemoport Insertion
Authors: Alam Shahbaz , Goel Nitesh , Bhasin Nikhil , Modi Shikha , Kaur Charanjeet
Published: May 2023

Background:

Chemotherapy through peripheral intravenous cannula causes severe thrombophlebitis. Chemoport is a best and favorable alternative for the same. It is done under local infiltration along with monitored anesthesia care with sedation. However, due to the lack of any fixed regimen, overt to under sedation is more common. To maintain an effective, consistent, and continuous level of sedation, we compared dexmedetomidine and propofol infusion in patients requiring monitored anesthesia care (MAC) for chemoport insertion.

Methodology:

Fifty patients posted for internal jugular vein chemoport insertion were randomly distributed into two groups: the propofol group and dexmedetomidine group. In Group P-injection, propofol infusion started at 125 μg/kg/min. Once observer's OAAS score 3 was achieved, propofol infusion was reduced to 25–75 μg/kg/min, whereas in Group D-Injection, dexmedetomidine bolus infusion was started at 1 μg/kg for 10 min and followed by 0.3–0.7 μg/kg/h and titrated to an OAAS score of 3.

Results:

OAAS score 3 was achieved significantly earlier in the propofol group as compared to the dexmedetomidine group (3.12 ± 1.7 vs. 8.04 ± 2.07, respectively). We were also able to maintain the desired sedation level throughout the procedure. Satisfaction scores in both the groups were comparable and patients in both the groups were hemodynamically stable throughout the procedure.

Conclusion:

In the current study, we found that propofol infusion was better regarding early onset and maintenance of OAAS score 3 with no requirement of rescue sedation during the procedure. The hemodynamic parameters and satisfaction scores were comparable in both groups. Hence, we suggest the use of injection propofol infusion for MAC under sedation in a patient requiring internal jugular vein chemoport insertion when compared to dexmedetomidine.
Anisocoria under Anesthesia
Authors: Kerai Sukhyanti , Goswami Surbhi , Gaba Prachi , Bhatt Garima
Published: May 2023

Anisocoria observed under anaesthesia is an alarming sign for anaesthesiologist and is suggestive of possible of neurological involvement due to raised intracranial pressure, intracranial hemorrhage, or space occupying lesions. We report the occurrence of new onset anisocoria in a patient undergoing video assisted thoracoscopic surgery under anaesthesia. The various etiologies of anisocoria under anaesthesia and their implication have been discussed.
A prospective observational study of changes in intraocular pressure before and after cataract surgery using noncontact tonometer in small incision cataract surgery and phacoemulsification
Authors: Kesireddy Alekya , Vivekanand Undrakonda , Lobo Sarita
Published: May 2023

Purpose:

To compare the changes in intraocular pressure (IOP) before and after cataract extraction using noncontact tonometer (NCT) in small incision cataract surgery (SICS) and phacoemulsification.

Materials and Methods:

A prospective observational study of 100 eyes that underwent phacoemulsification and 100 eyes that underwent SICS with intraocular lens implantation for senile cataract with normal IOP were included. Both groups underwent IOP recording using NCT, preoperatively, postoperatively at the 1st, 4th, and 6th weeks, respectively. Repeated-measure analysis of variance and independent sample t-test were applied to analyze the data.

Results:

The mean IOP at the preoperative and postoperative 1st, 4th, and 6th weeks was 13.07, 12.24, 11.78, and 11.66 mmHg, respectively, in SICS group and 14.39, 13.94, 13.08, and 12.90 mmHg in phacoemulsification groups, respectively (P < 0.001).

Conclusion:

A decline in postoperative IOP was present in both SICS and phacoemulsification groups, but a more significant decline was noticed in SICS group.
Bilateral lens coloboma in Marfans syndrome
Authors: Patel Megha B. , Nene Amit S. , Patil Lomesh D. , Shah Sonal , Shah Smitesh , Pirdankar Onkar H.
Published: May 2023

A 20-year-old male with Marfans syndrome complained of gradual progressive diminution of vision in the right eye (RE) for 6 months. A slit-lamp examination revealed bilateral inferior lenticular coloboma with cataractous changes involving the visual axis in RE. The patient underwent phacoemulsification with a foldable intraocular lens and capsular tension ring implantation in view of zonular dehiscence in the RE. Other eye was managed conservatively.
Ischemic optic neuropathy in chronic myelogenous leukemia presenting as unilateral optic disc edema
Authors: Nagpal Aniza , Moharana Bruttendu , Sharma Ria , Sharma Bhavana
Published: May 2023

Optic neuropathy in leukemia can occur due to infiltration by malignant cells, infection, ischemia, increased intracranial tension, and effects of chemotherapy or radiotherapy. Isolated optic nerve (ON) involvement is a rare presentation of chronic myelogenous leukemia (CML). It is important to differentiate between various etiopathogenesis of ON involvement in the setting of CML so that cause-specific treatment can be provided. Patients with ophthalmic manifestations of CML have been reported to have a lower 5-year survival rate. The complete blood count is an important investigation in all cases of disc edema to guide in the direction of any unusual systemic cause. Here, we present a case where the patient presented with unilateral disc edema, which led to the diagnosis of CML.
Thyroid hormone status during pregnancy in Bangladesh
Authors: Shahid Mohammad Moin , Islam Fatema Binte , Begum Shamima
Published: May 2023

Background:

Pregnancy is a physiological condition where early detection of any pathological change of thyroid hormone is very important to prevent complications. Population-specific thyroid hormone reference intervals are a key to this. Since Bangladesh is yet to develop such reference intervals, the aim of this study was to establish trimester-specific reference intervals addressing the physiological changes of thyroid hormone during pregnancy for Bangladeshi women.

Materials and Methods:

One thousand nine hundred and thirty-seven women with singleton pregnancy consuming iodinated salt were selected for this cross-sectional study. Participants having a history of thyroid disorder (TD), any illness influencing thyroid function, presence of goiter, recent history of consumption of thyroid status-altering medications, family history of TDs, and presence of thyroid antibodies were excluded from the study. 1038 pregnant women with thyroid-stimulating hormone (TSH) level within normal (nonpregnant) laboratory reference value (0.35–5.5 mIU/mL) were considered eligible for the study.

Results:

The mean age of the eligible cases was 28.06 ± 4.633 years ranging from 18 years to 42 years. The mean gestational ages of the study population while checking thyroid function were 8.83 ± 2.344 weeks, 19.99 ± 4.824 weeks, and 31.77 ± 2.123 weeks during 1st, 2nd, and 3rd trimesters, respectively. TSH level raised significantly from 1st trimester to 2nd trimester (1.85 ± 1.00 vs. 2.03 ± 1.02; P = 0.018) but the decline in 3rd trimester comparing to 2nd trimester (2.03 ± 1.02 vs. 1.90 ± 0.90; P = 0.071) was not statistically significant. The 2.5th–97.5th percentiles of TSH level of the study population were 0.440–4.050 mIU/mL, 0.531–4.570 mIU/mL, and 0.622–3.917 mIU/mL in 1st, 2nd, and 3rd trimesters, respectively.

Conclusion:

Reliance on nonpregnant reference intervals or any generalized gestational reference interval can hinder the desired progression of pregnancy influencing diagnosis and management for TDs in case of certain populations. Establishment of individual reference intervals for thyroid hormone in pregnancy bears great clinical importance for every population.
Thyrovigilance for hypothyroidism in India
Authors: Bajaj Sarita
Published: May 2023

Among endocrine abnormalities, thyroid diseases are the commonest both in India and worldwide. However, the prevalence of hypothyroidism in India is more than twice as high compared to its Western counterparts. Therefore an efficient and effective strategy to manage the disease in India is necessary. We reviewed published literature to determine the prevalence, and identify the challenges in the screening and management of hypothyroidism in India. A review of published literature indicates that nearly one-third of the patients with hypothyroidism across age groups remain undiagnosed and untreated in various regions of India. Based on the critical evaluation of these data from India, we have suggested certain best practices for screening, timely diagnosis, and the treatment of hypothyroidism. Primarily non-specific presentation necessitates a high index of suspicion to detect hypothyroidism in neonates and the juvenile population. An individualized approach is key in managing adult patients with hypothyroidism. In elderly patients recognizing hypothyroidism and its treatment, are challenging due to comorbidities and concomitant medications respectively. When managing any age group with hypothyroidism or subclinical hypothyroidism, clinicians should encourage patients for regular follow-up visits. With timely diagnosis delays in treatment and serious sequelae can be averted.
The role of ROX index–based intubation in COVID-19 pneumonia: a cross-sectional comparison and retrospective survival analysis
Authors: Vergis Sara , Philip Sam , Paul Vergis , George Manjit , Philip Nevil C , Tomy Mithu
Published: May 2023

Background: Coronavirus disease 2019 (COVID-19) patients with acute respiratory failure who experience delayed initiation of invasive mechanical ventilation have poor outcomes. The lack of objective measures to define the timing of intubation is an area of concern. We investigated the effect of timing of intubation based on respiratory rate-oxygenation (ROX) index on the outcomes of COVID-19 pneumonia. Methods: This was a retrospective cross-sectional study performed in a tertiary care teaching hospital in Kerala, India. Patients with COVID-19 pneumonia who were intubated were grouped into early intubation (within 12 hours of ROX index <4.88) or delayed intubation (12 hours or more hours after ROX <4.88). Results: A total of 58 patients was included in the study after exclusions. Among them, 20 patients were intubated early, and 38 patients were intubated 12 hours after ROX index <4.88. The mean age of the study population was 57±14 years, and 55.0% of the patients were male; diabetes mellitus (48.3%) and hypertension (50.0%) were the most common comorbidities. The early intubation group had 88.2% successful extubation, while only 11.8% of the delayed group had successful extubation (P<0.001). Survival was also significantly more frequent in the early intubation group. Conclusions: Early intubation within 12 hours of ROX index <4.88 was associated with improved extubation and survival in patients with COVID-19 pneumonia.
Evaluating diaphragmatic dysfunction and predicting non-invasive ventilation failure in acute exacerbation of chronic obstructive pulmonary disease in India
Authors: Patel Nupur B , Jain Gaurav , Chauhan Udit , Bhadoria Ajeet Singh , Chandrakar Saurabh , Indulekha Haritha
Published: May 2023

Background: Baseline diaphragmatic dysfunction (DD) at the initiation of non-invasive ventilation (NIV) correlates positively with subsequent intubation. We investigated the utility of DD detected 2 hours after NIV initiation in estimating NIV failure in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients. Methods: In a prospective-cohort design, we enrolled 60 consecutive patients with AECOPD initiated on NIV at intensive care unit admission, and NIV failure events were noted. The DD was assessed at baseline (T1 timepoint) and 2 hours after initiating NIV (T2 timepoint). We defined DD as ultrasound-assessed change in diaphragmatic thickness (ΔTDI) <20% (predefined criteria [PC]) or its cut-off that predicts NIV failure (calculated criteria [CC]) at both timepoints. A predictive-regression analysis was reported. Results: In total, 32 patients developed NIV failure, nine within 2 hours of NIV and remaining in next 6 days. The ∆TDI cut-off that predicted NIV failure (DD-CC) at T1 was ≤19.04% (area under the curve [AUC], 0.73; sensitivity, 50%; specificity, 85.71%; accuracy; 66.67%), while that at T2 was ≤35.3% (AUC, 0.75; sensitivity, 95.65%; specificity, 57.14%; accuracy, 74.51%; hazard ratio, 19.55). The NIV failure rate was 35.1% in those with normal diaphragmatic function by PC (T2) versus 5.9% by CC (T2). The odds ratio for NIV failure with DD criteria ≤35.3 and <20 at T2 was 29.33 and 4.61, while that for ≤19.04 and <20 at T1 was 6, respectively. Conclusions: The DD criterion of ≤35.3 (T2) had a better diagnostic profile compared to baseline and PC in prediction of NIV failure.
Comparison of safety and efficacy between therapeutic or intermediate versus prophylactic anticoagulation for thrombosis in COVID-19 patients: a systematic review and meta-analysis
Authors: Lee Hyeon-Jeong , Jang Hye Jin , Choi Won-Il , Joh Joonsung , Kim Junghyun , Park Jungeun , Choi Miyoung
Published: May 2023

Background: Patients with coronavirus disease 2019 (COVID-19) infections often have macrovascular or microvascular thrombosis and inflammation, which are known to be associated with a poor prognosis. Heparin has been hypothesized that administration of heparin with treatment dose rather than prophylactic dose for prevention of deep vein thrombosis in COVID-19 patients. Methods: Studies comparing therapeutic or intermediate anticoagulation with prophylactic anticoagulation in COVID-19 patients were eligible. Mortality, thromboembolic events, and bleeding were the primary outcomes. PubMed, Embase, the Cochrane Library, and KMbase were searched up to July 2021. A meta-analysis was performed using random-effect model. Subgroup analysis was conducted according to disease severity. Results: Six randomized controlled trials (RCTs) with 4,678 patients and four cohort studies with 1,080 patients were included in this review. In the RCTs, the therapeutic or intermediate anticoagulation was associated with significant reductions in the occurrence of thromboembolic events (5 studies, n=4,664; relative risk [RR], 0.72; P=0.01), and a significant increase in bleeding events (5 studies, n=4,667; RR, 1.88; P=0.004). In the moderate patients, therapeutic or intermediate anticoagulation was more beneficial than prophylactic anticoagulation in terms of thromboembolic events, but showed significantly higher bleeding events. In the severe patients, the incidence of thromboembolic and bleeding events in the therapeutic or intermediate. Conclusions: The study findings suggest that prophylactic anticoagulant treatment should be used in patients with moderate and severe COVID-19 infection groups. Further studies are needed to determine more individualized anticoagulation guidance for all COVID-19 patients.
Prognostic significance of respiratory quotient in patients undergoing extracorporeal cardiopulmonary resuscitation in Korea
Authors: Lee Yun Im , Ko Ryoung-Eun , Na Soo Jin , Ryu Jeong-Am , Cho Yang Hyun , Yang Jeong Hoon , Chung Chi Ryang , Suh Gee Young
Published: May 2023

Background: Respiratory quotient (RQ) may be used as a tissue hypoxia marker in various clinical settings but its prognostic significance in patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) is not known. Methods: Medical records of adult patients admitted to the intensive care units after ECPR in whom RQ could be calculated from May 2004 to April 2020 were retrospectively reviewed. Patients were divided into good neurologic outcome and poor neurologic outcome groups. Prognostic significance of RQ was compared to other clinical characteristics and markers of tissue hypoxia. Results: During the study period, 155 patients were eligible for analysis. Of them, 90 (58.1%) had a poor neurologic outcome. The group with poor neurologic outcome had a higher incidence of out-of-hospital cardiac arrest (25.6% vs. 9.2%, P=0.010) and longer cardiopulmonary resuscitation to pump-on time (33.0 vs. 25.2 minutes, P=0.001) than the group with good neurologic outcome. For tissue hypoxia markers, the group with poor neurologic outcome had higher RQ (2.2 vs. 1.7, P=0.021) and lactate levels (8.2 vs. 5.4 mmol/L, P=0.004) than the group with good neurologic outcome. On multivariable analysis, age, cardiopulmonary resuscitation to pump-on time, and lactate levels above 7.1 mmol/L were significant predictors for a poor neurologic outcome but not RQ. Conclusions: In patients who received ECPR, RQ was not independently associated with poor neurologic outcome.