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Possibly the oldest fish-made resting traces
No full textThe Silurian Sharawra Member (middle to late Llandoverian) in Saudi Arabia exhibits unique surface traces with exceptional preservation: Seven small, wing-shaped traces occur on a sandstone slab showing well-defined hummocky cross-stratification having a few decimeters wavelength being covered by a thin mud layer. These traces are preserved as concave epirelief along with elongated internal striae and surrounded by slightly elevated levees. Preservation of these delicate, 10-20 mm long and similar to 10 mm wide traces suggests that they were formed after a storm event when mud had already settled to the sediment surface. The lack of wave-generated sedimentary structures implies deposition between fair-weather and storm-wave base probably preventing further rapid reworking by waves. Based on their geometry, internal pattern, and spatial distribution, these wing-shaped traces are interpreted to have been produced by relatively stationary bottom-feeding fish, morphologically similar to ancestors of Gobiidae, probably in the Actinopterygii class. The majority of fish-made trace fossils record feeding and locomotion behaviour, whereas the wing-shaped traces are interpreted to represent resting structures made by fish that pressed their fins downward on the muddy sediment surface and hence, represent undertracks. These traces are possibly the oldest fish-made structure documented thus far. These wing-shaped traces are described as Pisquiesichnus dashtgardi igen. et isp. nov. in this study
Is Fat Deposition of Renal Sinus a Concomitant Finding to Fatty Liver Disease? The First Study Regarding the Relationship Between Kidney and Liver Fat Content with Non-Contrast Computed Tomography
No full textIntroduction: It has been established that abnormal fat deposits are associated with fat deposition in other abdominal regions and linked to obesity, diabetes mellitus, hypertension, vascular and metabolic diseases. This study aimed to determine whether there was a relationship between fat deposition of the renal (i.e., kidney) sinus (FRS) and fatty liver disease (FLD) in a sample of adults. The authors hypothesized that FRS could be a diagnostic finding associated with Hepatosteatosis (HS) in a sample of younger patients. This study was the first apparent investigation of this possible phenomenon.
Methods: A convenience sample of 92 adult patients of which 19 (20.7%) were females and 73 (79.3%) were males, and with a mean age of 30.19 (SD = 6.00) were included. The authors calculated Hounsfield Units (HU) (i.e., relative quantitative measurement of radio density) of patients' livers and spleens on non-contrast computed tomography (CT). Liver and spleen differences < 10 HU were considered steatosis (FLD). The authors stratified sample patients into two analytic subgroups according to the presence of FLD or not and compared them based on their FRS widths.
Results: In the FLD subgroup (N = 48), the difference of HU values between liver and spleen was -5.19 (SD = 11.32), with a range of -38 - 8 HU, while, in the non-steatosis subgroup (N = 44), the mean difference was 16.36 (SD = 3.90), range of 11 - 26 HU. The average diameter of FRS width was 12.5 mm in those patients with steatosis (FLD subgroup) although 9.3 mm in non-FLD patients. (p = 0.02).
Conclusions: Based on these results, FRS may be able to be used by radiologists as an ancillary method in the detection of hepatic steatosis in younger adults. The effectiveness of premedical processes (e.g., exercise and diet modification) can also be increased by non-radiologists after detection of lower-grade HS
Optical Coherence Tomography Angiography Findings in Primary Open-Angle and Pseudoexfoliation Glaucoma
No full textObjectives: To compare the optical disc and macular vascular density values of patients with glaucoma and healthy individuals by using optical coherence tomography angiography and evaluate the relationship between structural and functional test results and vascular density.
Materials and methods: The study included 128 eyes in total: 31 with pseudoexfoliation glaucoma (PEG), 55 with primary open-angle glaucoma (POAG) and similar visual field defects, and 42 healthy eyes. Whole image peripapillary vessel density (wpVD), intradisc vessel density (idVD), peripapillary vessel density (pVD), whole image macular vessel density (wmVD), and parafoveal vessel density (pfVD) values were compared between the groups. Correlations between visual field findings, retinal nerve fiber layer (RNFL) and optic nerve head measurements and peripapillary and macular vascular density were analyzed.
Results: In the PEG and POAG groups, wpVD, idVD, wmVD, and pfVD values were significantly lower in than the control group. In the PEG group, wpVD was found to be significantly lower than the POAG group (p<0.001). There was no significant difference between the PEG and POAG groups in wmVD and pfVD except for nasal pfVD. There were strong positive correlations between RNFL thickness and pVD in the glaucoma groups (p<0.001). Significant correlations were found between visual field mean deviation and pattern standard deviation values and peripapillary and macular vessel density values in the glaucoma groups.
Conclusion: Vascular density values were lower in glaucoma patients compared to normal individuals, and there is a strong correlation between structural and functional tests and vessel density values. The lower vascular density in the PEG group compared to the POAG group indicates that vascular damage may be more common in PEG patients
The Longitudinal Evolution of Post-COVID-19 Outcomes Among Hemodialysis Patients in Turkey
No full textBackground: Hemodialysis (HD) patients have increased risk for short-term adverse outcomes of COVID-19. However, complications and survival at the post-COVID-19 period have not been published extensively.
Methods: We conducted a national, multicenter observational study that included adult maintenance HD patients recovered from confirmed COVID-19. A control HD group without COVID-19 was selected from patients in the same center. We investigated the characteristics and outcomes in the follow-up of HD patients and compare them with the non-COVID group.
Results: A total of 1223 patients (635 patients in COVID-19 group, 588 patients in non-COVID group) from 47 centers were included in the study. The patients' baseline and HD characteristics were almost similar. 28th day mortality and mortality between 28th day-90th day were higher in the COVID-19 group than non-COVID group [19 (3.0%) patients vs. none (0%); 15 (2.4%) patients vs. 4 (0.7%) patients, respectively]. The presence of respiratory symptoms, rehospitalization, need for home oxygen therapy, lower respiratory tract infection, A-V fistula thrombosis were significantly higher in the COVID-19 group in both the first 28 days and between 28-90 days. In the multivariable analysis, age [Odds ratio (OR) (95% confidence interval[CI]): 1.029(1.004-1.056)], group (COVID-19 group vs. non-COVID group) [OR (95%CI): 7.258(2.538-20.751) and vascular access type (tunneled catheter/AV fistula) [OR(95%CI): 2.512 (1.249-5.051)] were found as independent parameters related to 90-day mortality.
Conclusion: In the post-COVID period, maintenance HD patients who have had COVID-19 have increased rehospitalization, respiratory problems, vascular access problems, and high mortality compared to the non-COVID HD patients
DEMOGRAPHIC DIFFERENCES MATTER ON JOB OUTCOMES: PSYCHOLOGICAL CONTRACT'S MEDIATING ROLE
No full textPurpose - Drawing upon prior researches on the social exchange theory, we examine the effect of employee demographic variables on psychological contract fulfillment, which eventually influences employee's job satisfaction, intention to leave, organizational citizenship behavior, cynicism, and task performance.
Research methodology - Data from 274 employees of different manufacturing enterprises has been collected through the survey. Description and interpretation statistics are used through SPSS and also AMOS. Structural equality modeling is used to assess the psychological contract's mediating function.
Findings - Data analysis shows that psychological contract fulfillment mediated positive relationships between demographic variables and constructive job outcomes; in contrast, mediated negative relationships between demographic variables and destructive job outcomes.
Research limitations - This paper applies data from the manufacturing industry operating in Turkey, which may prevent the generalizability of the paper. More study is needed to confirm these results on different samples in order to generalize findings. In addition, the data comes from a single source, raising the risk of common technique bias, and is focused solely on self-reports.
Practical implications - The study suggests that organizations review and revise their ideas on the exchange connection with their workforce as job outcomes of employees are connected to PC fulfillment. In practice, managers and leaders may highlight that such fulfillment constitutes an investment of resources into and a long-term commitment to the employee in addition to satisfying relational responsibilities. Leaders should place a strong emphasis on increasing employee commitment levels. Creating a culture of trust and loyalty fosters beneficial behavioral and attitudinal results among employees
Editorial
No full textSpecies introductions are a major concern for ecosystem functioning, socio-economy and human well-being (Vilà et al. 2010; Lockwood et al. 2013; Diagne et al. 2021; Zenni et al. 2021). However, despite measures for prevention and control, a large number of non-native species have been identified in the last decades worldwide in both aquatic and terrestrial environments (IPBES 2019; Lowe et al. 2000; Guo et al. 2021). Although preventing introductions has proved to be the most effective management strategy (Wittenberg and Cock 2001; Pergl et al. 2016), extant non-native species are still expanding their distributional range and new non-native species are being recorded (Seebens et al. 2017). Non-native species introduced into new environments may represent a serious ecological and economical threat, especially if they spread rapidly in a new region and thus become invasive (Ricciardi et al. 2021; Cuthbert et al. 2021). Further, geographical areas that act as biodiversity hotspots with a high level of endemism are especially threatened by invasive species (Ribeiro and Leunda 2012). Hence, the identification of those non-native species that are likely to become invasive may be of crucial importance for the development of prevention measures, which can be achieved by risk screening studies (Adams and Lee 2012
Applying decision tree algorithm to explore occupational injuries in the Turkish construction industry
No full textOccupational injuries and fatalities are one of the most significant issues in the construction industry. Variables, such as workers’ behavior, age, worksite condition, and type of activity, play key roles in the occurrence of construction accidents. In recent years, data mining techniques have been successfully used not only in health, economy, and social sciences, but also in construction-related fields. In this study, C5.0 decision tree algorithm was used to analyze the accident data obtained from the Social Security Institution of Turkey. A classification tree model was created to discover the associations between the attributes. The results show the relationship between the injury status of workers and the attributes, and the accuracy rate of the model was 70.26%. Meanwhile, according to findings, unsafe conditions, type of accident, and activity type were the most important attributes in the model. Furthermore, the predictor importance of the attributes was compared, and several outcomes were discovered; for instance, the workers’ educational background has greater predictive power than age. On the other hand, the branches of the decision tree pointed out several attribute sequences due to their high rated serious/fatal injury rates. The results of this study can be used in the prevention and mitigation strategies for construction accidents
Microalbuminuria and its Prognostic Significance in Patients with Acute Heart Failure with Preserved, Mid-Range, and Reduced Ejection Fraction
No full textBackground: The prevalence and significance of microalbuminuria have not been well studied in patients with different heart failure subtypes.
Objective: The prevalence and significance of microalbuminuria have not been well studied in patients with different heart failure subtypes. Therefore, we aimed to investigate the frequency and prognostic value of microalbuminuria in patients hospitalized for acute heart failure (AHF) with preserved ejection fraction (HFpEF), mid-range ejection fraction (HFmrEF), and reduced ejection fraction (HFrEF).
Methods: All consecutive adult patients referred to the hospital due to AHF between June 2016 and June 2019 were enrolled. Microalbuminuria is defined as urinary albumin to creatinine ratio (UACR) level in the range of 30-300 mg/g. Hospital mortality was the endpoint of this study.
Results: Of the 426 AHF patients (mean age 70.64 ± 10.03 years, 53.3 % female), 50% had HFrEF, 38.3% had HFpEF, and 11.7% had HFmrEF at presentation.The prevalence of microalbuminuria was 35.2%, 28.8%, and 28.0% in HFrEF, HFpEF, and HFmrEF, respectively. A total of 19 (4.5%) patients died during the in-hospital course, and in-hospital mortality was higher in HFrEF patients (6.6%) compared to patients with HFpEF (2.5%) and HFmrEF (2.0%). Multivariate analysis showed that the presence of microalbuminuria predicted in-hospital mortality in patients with HFrEF and HFmrEF but not in HFpEF.
Conclusion: Although microalbuminuria was common in all subgroups of AHF patients, it has been found to predict prognosis only in patients with HFrEF and HFmrEF
Lumpectomy with or without Irradiation in Women 70 Years of Age or Older with the Early Breast Cancer
No full textOBJECTIVE
The incidence of breast cancer increases with age. The treatment of elderly breast cancer patients is not standardized.
METHODS
A total of 70 patients aged 70 years and older who were diagnosed with histopathologically T1-2 breast cancer between June 2005 and August 2021 were retrospectively evaluated. All patients underwent breast-conserving surgery. The patient groups who received and did not receive adjuvant radiotherapy were compared. The primary endpoint of the study was ipsilateral breast tumor recurrence-free survival. The study's secondary endpoints were breast cancer-specific survival and distant metastasis-free survival.
RESULTS
The median age was 73 (70-82). Adjuvant radiotherapy was applied in 53 patients (75.7%). Radiotherapy application decreased with age (70-76 years vs. 77-82 years) (p=0.023). The median follow-up was 42 months (3-169). Five patients had ipsilateral breast recurrence during the follow-up, one patient had regional recurrence (axilla), three patients had distant metastases, and nine died. Two of the patients died of breast cancer, and seven patients died from other causes. There were no differences in recurrence and death rates in patients who received and did not receive radiotherapy. Median overall survival was 119 months (94-145) in the radiotherapy arm and 141 months (136-167) in the non-irradiated arm; the 5-year OS was 81% and 100%, respectively (p=0.078). The 5-year BCSS was 97% in the radiotherapy group and 100% in the non-irradiated group (p=0.222); PFS 83% and 84% (p=0.622); IBTRFS 87% and 100% (p=0.113); and DMFS 93% and 100%, respectively (p=0.275). A statistically significant association was found between hormonal subtypes and DMFS. Five-year DMFS was 67% in triple (-) group, 93% in HR (+) HER2 (-) group, and 100% in HER2 (+) group (p=0.036).
CONCLUSION
Radiotherapy usage decreased with age. There were no differences in recurrence and death rates in patients who received and did not receive radiotherapy. Most of the deaths were due to causes other than breast cancer
Forming a Decentralized Research Network: DS4H
No full textThere is a trend toward decentralized systems, but these systems are developed without conducting enough software tests. Also, the performance, scalability, and sustainability of the decentralized systems are not taken into account. One of the reasons is the time-consuming testing process. The other is the hardware requirements and the complexity of the software installations of the testing environment. Developer communities need stable and secure research networks to test and develop prototypes before releasing the working versions. Cloud-based blockchain test networks are available, but it allows using a specific framework. Also, users are required to learn how to use each framework. Blockchain test networks use public ledgers, and this is also not preferable in many project implementations because of privacy reasons. Testbeds are inflexible and unrealistic in terms of scalability and performance. There is a need for a physical test network to create a realistic test environment. This study aims to form a sustainable and scalable research environment where decentralized technologies are researched and developed. The method of this study will include three stages to create a decentralized research network. The first stage is to develop the decentralized foundation of the network by using the Quorum blockchain framework and RAFT consensus protocol. Node requirements are simplified to run on low-cost devices. The second stage will be to develop a web-based platform to serve as an efficient way for the developers to deploy smart contracts easily. The final stage will be ensuring the sustainability of the system. Usage policy is formed that includes management of the network, the system usage rules, and regulations. A decentralized governance model is proposed. Smart contracts are developed to manage and ensure the sustainability of the research network. The available test tools were not sufficient and not flexible to use in this system, so a new test tool was developed for this project. The new test tool will verify the research environment with scalability, latency, and performance tests. As a result, the "Decentralized Solutions for Humanity" (DS4H) research network is deployed in four different regions of Turkey. This network is tested with four initial nodes. New nodes are to be added worldwide. The developed tools named Chainex, GoHammer, and Scanner are shared as open-source. Future works will include adding multiple blockchain network support, working on consensus protocols and new decentralized services. Finally, the DS4H research network provides a test and development research environment for blockchain projects with sustainable and low-cost maintenance