bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and Formation of Zeolite 5A from Local Kaolin Clay for Drying and Desuphurization of Liquefied Petroleum Gas
Authors: A. Mohammed Abdul-Halim , K. Nassrullah Zeinab
Published: July 2023

This work deals with preparation of zeolite 5A from Dewekhala kaolin clay in Al-Anbar region for drying and desulphurization of liquefied petroleum gas. The preparation of zeolite 5A includes treating kaolin clay with dilute hydrochloric acid 1N, treating metakaolin with NaOH solution to prepare 4A zeolite, ion exchange, and formation. For preparation of zeolite 4A, metakaolin treated at different temperatures (40, 60, 80, 90, and 100 °C) with different concentrations of sodium hydroxide solution (1, 2, 3, and 4 N) for 2 hours. The zeolite samples give the best relative crystallinity of zeolite prepared at 80 °C with NaOH concentration 3N (199%), and at 90 and 100°C with NaOH concentration solution 2N (184% and 189%, respectively). Zeolite 5A was prepared by ion exchange of zeolite 4A prepared at 90°C and 2N NaOH concentration with 1.5 N calcium chloride solution at 90 °C and 5 hours, the ion exchange percentage was 66.6%. The formation experiments included mixing the prepared powder of 5A zeolite with different percentages of kaolin clay, citric acid and tartaric acid to form an irregular shape of zeolite granules. Tartaric acid binder gives higher bulk crushing strength than that obtained by using citric acid binder with no significant difference in the surface area. 7.5 weight% tartaric acid binder has the higher bulk crushing strength 206 newton with surface area 267.4 m2/g. Kaolin clay binder with 15 weight% gives the highest surface area 356 m2/g with bulk crushing strength 123 newton, it was chose as the best binder for zeolite 5A. The prepared granules of 5A zeolite were used for the adsorption experiments of H2O, and H2S contaminants from LPG. Different flow rates of LPG (3, 4, and 5 liter/minute) were studied. It was found that H2O is the strongly adsorbed component and H2S is the weakly adsorbed component. The best flow rate in this work for H2O, and H2S adsorption is 5 liter/minute of LPG. The adsorption capacity for H2O was 7.547 g/g and for H2S was 1.734 g/g.
Zinc Element Traces to Inhibit Scale Formation on Cooling Tower and Air Cooler Systems
Authors: Abdul Rahman Ahmed Reshan Shaymaa
Published: July 2023

Calcium carbonate is predominantly present in aqueous systems, which iscommonly used in industrial processes. It has inverse solubility characteristicsresulting in the deposition of scale on heat transfer surface. This paper focuses ondeveloping methods for inhibition of calcium carbonate scale formation in coolingtower and air cooler system where scaling can cause serious problems, ZnCl 2 and ZnI2 has been investigated as scale inhibitor on AISI 316 and 304. ZnCl 2 were moreeffective than ZnI 2 in both systems, and AISI 316 show more receptivity to thechlorides salt compared to AISI 304. The inhibitors were more effective in coolingtower than air cooler system. AISI 316 show more constant inhibition efficiency incooling tower with maximum of 95% with ZnCl 2 and 83% with ZnI 2 .
Reverse Osmosis Polyamide Membrane for the Removal of Blue and Yellow Dye from Waste Water
Authors: Mustafa H. AL – Nakib Nada
Published: July 2023

The present work aims to study the removal of dyes from wastewater by reverse osmosis process. Two dyes were used direct blue 6, and direct yellow. Experiments were performed with feed concentration (75 – 450 ppm), operation temperature (30 – 50 oC) and time (0.2 – 2.0 hr). The membrane used is thin film composite membrane (TFC). It was found that modal permeate concentration decreases with increasing feed concentration and time operating, while permeate concentration increases with increasing feed temperature. Also it was found that product rate increase with increasing temperature, but it decrease with increasing feed concentration and time. The concentration of reject solution showed an increase with increasing feed concentration of dyes and feed temperature, while decreases with increasing time operating of reverse osmosis unit. The maximum rejection for direct blue 6 and direct yellow are 98.89% and 98.30% respectively. The maximum recovery percentage for direct blue 6 and direct yellow are 17.84% and 18.20% respectively. The maximum concentration factor of direct blue 6 is 1.227 and for direct yellow is 1.272.
Removal of Phenolic Compounds from Aqueous Solution by Using Agricultural Waste (Al-Khriet)
Authors: A.K. Al-jandeel Hayder
Published: July 2023

Adsorption techniques are widely used to remove organics pollutants from waste water particularly, when using low cost adsorbent available in Iraq. Al-Khriet powder which was found in legs of Typha Domingensis is used as bio sorbent for removing phenolic compounds from aqueous solution. The influence of adsorbent dosage and contact time on removal percentage and adsorb ate amount of phenol and 4- nitro phenol onto Al-Khriet were studied. The highest adsorption capacity was for 4-nitrophenol 91.5% than for phenol 82% with 50 mg/L concentration, 0.5 gm. dosage of adsorbent and pH 6 under a batch condition. The experimental data were tested using different isotherm models. The results show that Freundlich model resulted in the best fit also the kinetic study make it clear that the adsorption process proceeded according to the pseudo second order model.
Mass Transfer Enhancement Using Extensions as Turbulence Promoters
Authors: Slaiman Q.J.M. , S. Ahmed Buraq
Published: July 2023

Mass transfer was studied using a rotating cylinder electrode with different lengths of legs acting as turbulence promoters. Two types of rotating cylinder ,made of brass, were examined : an enhanced cylinder one, with four rectangular extensions 10 mm long, 10 mm wide, and 1mm thick, and an enhanced cylinder two with four longitudes 30 mm long,10 mm wide, and 1mm thick. The best performance was obtained for enhanced cylinder two at low rotation speeds while enhanced cylinder one was realized at high rotation speeds. The mass transfer enhancement as compared with a normal rotating cylinder electrode, devoid of promoters, is 53% or 58% higher. The enhancement percentage decreased as rotation speeds increased further, since, seemingly, full turbulence has been reached practically by means of rotation and turbulence promoters.
Corrosion Inhibition of Galvanic Couple Copper Alloy/Mild Steel in Cooling Water System
Authors: S. Yaro Aprael , A. Idan Munaf
Published: July 2023

The driving idea for the present work was to combine the effect of polyvinyl alcohol (PVA) as corrosion inhibitor with the distance between the anodic and cathodic elements of the galvanic cell, beside their area ratio, in scope of synergistic suppression of galvanic corrosion on Cu/Fe model couple, using weight loss method. The performance affecting galvanic corrosion process has been tested for three major factors affect the process:1. Four PVA inhibitor concentrations were selected to be (0, 1000, 4000 and 7000 ppm) in simulated cooling water.2. Two cathode: anode area ratios as 1:1 and 2.4:1.3. Two distances apart cathode – anode as 3 and 7 cm.Maximum corrosion inhibition achieved was 86% which indicates that increasing inhibitor concentration leads to decrease dissolution process followed hydrogen evaluation Cu electrode as cathode element in galvanic cell.
Permeability Prediction of Un-Cored Intervals Using FZI Method and Matrix Density Grouping Method: A Case Study of Abughirab Field/Asmari FM., Iraq
Authors: B. Alsinbili Mohammed , N. Aljawad Sameer , Awni Aldalawy Ammar
Published: July 2023

Knowledge of permeability is critical for developing an effective reservoir description. Permeability data may be calculated from well tests, cores and logs. Normally, using well log data to derive estimates of permeability is the lowest cost method. This paper will focus on the evaluation of formation permeability in un-cored intervals for Abughirab field/Asmari reservoir in Iraq from core and well log data. Hydraulic flow unit (HFU) concept is strongly related to the flow zone indicator (FZI) which is a function of the reservoir quality index (RQI). Both measures are based on porosity and permeability of cores. It is assumed that samples with similar FZI values belong to the same HFU. A generated method is also used to calculate permeability in un-cored zones depending on matrix density grouping, where each group has its own permeability-porosity correlation. After applying the both methods and correlating the calculated permeability with the core permeability data it revealed that matrix density grouping is the best method to calculate permeability in un-cored zones and it is better than FZI method in this field, then the estimated permeability is distributed through the members of Asmari reservoir in Abughirab field and it is concluded that permeability in this field is generally increases toward south culmination of Abughirab field.
Simulation of Batch Reactive Distillation for Biodiesel Production from Oleic Acid Esterification
Authors: B. Nakkash Nada , R. Al-Karkhi Sarah
Published: July 2023

The present work concerns with simulating unsteady state equilibrium model for production of methyl oleate (biodiesel) from reaction of oleic acid with methanol using sulfuric acid as a catalyst in batch reactive distillation. MESHR equations of equilibrium model were solved using MATLAB (R2010a). The validity of simulation model was tested by comparing the simulation results with a data available in literature. UNIQUAC liquid phase activity coefficient model is the most appropriate model to describe the non-ideality of OLAC-MEOH-MEOL-H2O system. The chemical reactions rates results from EQ model indicating the rates are controlled by chemical kinetics. Several variables was studied such as molar ratio of methanol to oleic acid 4:1, 6:1 and 8:1, amount of catalyst 0.6, 1.2 and 1.8 g sulfuric acid/g oleic acid, reaction time 36, 57 and 75 minutes, and reaction temperature 100, 120 and 130oC. Taguchi method based on signal to noise ratio was used to determine the best operating conditions for biodiesel production.
Structure Rheology of Polyethylene Oxide Solution
Authors: Omer Kashmola Talib , Saad Kamil Estabraq
Published: July 2023

Intrinsic viscosities have been studied for polyethylene oxide in water which has wide industrial applications. The polyethylene oxide samples had two different structures, the first one was linear and covers a wide range of molecular weight of 1, 3, 10, 20, 35, 99, 370, 1100, 4600, and 8000 kg/mol and the second one was branched and had molecular weights of 0.55 and 40 kg/mol.Intrinsic viscosities and Huggins constants have been determined for all types and molecular weights mentioned above at 25ºC using a capillary viscometer. The values of Mark-Houwink parameters (K and a) were equal to 0.0068 ml/g and 0.67 respectively, and have not been published for this range of molecular weight in as yet.
Estimation Liquid Permeability Using Air Permeability Laboratory Data
Authors: Abdulwahid Al-Sudani Jalal , Kaiser and Salam Rwaida , J. Al-Rubeai Salam
Published: July 2023

Permeability data has major importance work that should be handled in all reservoir simulation studies. The importance of permeability data increases in mature oil and gas fields due to its sensitivity for the requirements of some specific improved recoveries. However, the industry has a huge source of data of air permeability measurements against little number of liquid permeability values. This is due to the relatively high cost of special core analysis.The current study suggests a correlation to convert air permeability data that are conventionally measured during laboratory core analysis into liquid permeability. This correlation introduces a feasible estimation in cases of data loose and poorly consolidated formations, or in case of the unavailability of old cores to carry out liquid permeability. Moreover, the conversion formula offers a better use of the large amount of old air permeability data obtained through routine core analysis for the further uses in reservoir and geological modeling studies.The comparison analysis shows high accuracy and more consistent results over a wide range of permeability values for the suggested conversion formula.
Ethanol-Water Separation by Pressure Swing Adsorption (PSA)
Authors: A. Abdel-Rahman Zaid , M. Mahmood Abdulrahman , J. Ali Ahmed
Published: July 2023

Single long spiral tube column pressure swing adsorption (PSA) unit, 25 mm diameter, and 6 m length was constructed to study the separation of water from ethanol at azeotropic concentration of 95 wt%. The first three meters of the column length acted as a vaporizer and the remaining length acted as an adsorber filled by commercial 3A zeolite. The effect of pressure, temperature and feed flow rate on the product ethanol purity, process recovery and productivity were studied. The results showed that ethanol purity increased with temperature and pressure and decreased with feed flow rate. The purity decreased with increasing productivity. The purity range was 98.9 % to 99.6 %, the recovery range was 0.82 to 0.92 and the productivity range was 0.3 to 1.05 kg ethanol/kg zeolite.h.
Viscosity Reduction of Sharqi Baghdad Heavy Crude Oil Using Different Polar Hydrocarbons, Oxygenated Solvents
Authors: Qasim Hussein Hussein , Abdul-wahhab Mohammad Saja
Published: July 2023

This work studied the facilitation of the transportation of Sharqi Baghdad heavy crude oil characterized with high viscosity 51.6 cSt at 40 °C, low API 18.8, and high asphaltenes content 7.1 wt.%, by reducing its viscosity from break down asphaltene agglomerates using different types of hydrocarbon and oxygenated polar solvents such as toluene, methanol, mix xylenes, and reformate. The best results are obtained by using methanol because it owns a high efficiency to reduce viscosity of crude oil to 21.1 cSt at 40 °C. Toluene, xylenes and reformate decreased viscosity to 25.3, 27.5 and 28,4 cSt at 40 °C, respectively. Asphaltenes content decreased to 4.2 wt. % by using toluene at 110 °C. And best improvement in API of the heavy crude oil is 26.1 at 40 °C by using xylenes.
Experimental Determination of the Elastic and Viscous Behavior of Polycarbonate Melts at Different Temperatures and Their Relationship to the Steady State Viscosity via the Cox-Merz Rule
Authors: K. Muallah Shatha
Published: July 2023

Rheological instrument is one of the basic analytical measurements for diagnosing the properties of polymers fluids to be used in any industry. In this research polycarbonate was chosen because of its importance in many areas and possesses several distinct properties.Two kinds of rheometers devices were used at different range of temperatures from 220 ˚C-300 ˚C to characterize the rheological technique of melted polycarbonate (Makrolon 2805) by a combination of different investigating techniques. We compared the results of the linear (oscillatory) method with the non-linear (steady-state) method; the former method provided the storage and the loss modulus of melted polycarbonate, and presented the Cox-Merz model as well. One of the major problems in measuring the viscosity of polycarbonate at high shear rates, especially at the extremes of temperatures, was that during the use of the capillary rheometer, long molecule chains led to high viscosity.
Treatment of Slack Wax by Thermal Cracking Process
Authors: A.K Mohammed Abdul Halim , Mohammed Obeyed Saleem
Published: July 2023

This work deals with thermal cracking of slack wax produced as a byproduct from solvent dewaxing process of medium lubricating oil fraction in AL-Dura refinery. The thermal cracking process was carried out at a temperature ranges 480-540 ºC and atmospheric pressure. The liquid hourly space velocity (LHSV) for thermal cracking was varied between 1.0-2.5 . It was found that the conversion increased (61 - 83) with the increasing of reaction temperature (480 - 540) and decreased (83 - 63) with the increasing of liquid hourly space velocity (1.0 - 2.5).The maximum gasoline yield obtained by thermal cracking process (48.52 wt. % of feed) was obtained at 500 ºC and liquid hour space velocity 1 . The obtaining liquid product at the best operating condition 500 ºC and LHSV 1 was fractionated into wide range fractions. Based on the determination of some properties for the distilled fractions and comparison (these properties with that required by standard requirements) it is possible to use the fractions of cracking products as a component for production of automobile gasoline, domestic kerosene, light diesel fuel and basic lubricating oils.
Analytical Model for Detection the Tilt in Originally Oil Water Contacts
Authors: Abdulwahid Al-Sudani Jalal
Published: July 2023

Many carbonate reservoirs in the world show a tilted in originally oil-water contact (OOWC) which requires a special consideration in the selection of the capillary pressure curves and an understanding of reservoir fluids distribution while initializing the reservoir simulation models.An analytical model for predicting the capillary pressure across the interface that separates two immiscible fluids was derived from reservoir pressure transient analysis. The model reflected the entire interaction between the reservoir-aquifer fluids and rock properties measured under downhole reservoir conditions.This model retained the natural coupling of oil reservoirs with the aquifer zone and treated them as an explicit-region composite system; thus the exact solutions of diffusivity equation could be used explicitly for each region. The reservoir-aquifer zones were linked by a capillary transition zone that reflected the pressure difference across the free water level.The principle of superposition theorem was applied to perform this link across the free water level to estimate the reflected aquifer pressure drop behavior that holds the fluid contacts in their equilibrium positions.The results of originally oil water contact positions generated by the proposed model were compared with data obtained from a carbonate oil field; the results given by the model showed full agreement with the actual field data.
Coagulation/ Flocculation, Microfiltration and Nanofiltration for Water Treatment of Main Outfall Drain for Injection in Nasiriyah Oil Field
Authors: Faiq Al-Alawy Ahmed , Jabbar Madlool Jaafar
Published: July 2023

The present work aims to study the efficiency of coagulation/ flocculation as 1st stage, natural gravity water filter or microfiltration (MF) as 2nd stage and nanofiltration (NF) technology as final stage for treatment of water of main outfall drain (MOD) for injection in Nasiriyah oil field. Effects of operating parameters such as coagulant dosage, speed and time of slow mixing step and settling time in the 1st stage were studied. Also feed turbidity and total suspended solids (TSS) in the 2nd stage were studied. Also feed concentration, temperature and operating time, in the final stage were studied. The results showed that the optimum dosage for alum was 35, 40 and 50 ppm. While, for ferric chloride it was 15, 20 and 30 ppm and for polyelectrolyte 4, 8 and 10 ppm for 11.8, 30 and 100 NTU initial turbidity respectively. The optimum speed for the 2nd step was 25 rpm for each of alum 35 ppm, ferric chloride 15 ppm and polyelectrolyte 4 ppm. While the optimum time for the 2nd step was 30 min for each of alum 35 ppm, ferric chloride 15 ppm and polyelectrolyte 4 ppm and settling time was 30 min for each of alum 35 ppm, ferric chloride 15 ppm and polyelectrolyte 4 ppm. It was found that turbidity and TSS increases by increasing the inlet turbidity and TSS.

Also it was found that salts concentration in product increases by increasing feed concentration and temperature. Rejection percentages were (94.475 – 95.631 %), (88.088 – 90.714 %), (83.33 – 93.2 %), (85.116 – 92.727 %) and (65.385 – 72.727 %) for sulphate, total hardness (TH), Ca2+, Mg2+ and Cl- respectively and recovery percentage of product water was (11.429 – 38.143 %) for polyamide membrane (TFC). In the case of concentrate recirculation, feed concentration, permeate concentration and volume of permeate increases with increasing in operating time and 12.69 liter of water valid for injection in oil field was recovered from 25 liter feed after 180 minute.
PREPARATION OF PVC HOLLOW FIBER MEMBRANE USING (DMAC/ACETONE)
Authors: M. Hussein Fawziea , S. Merzah Amel , Rashad Zaid Waadulla
Published: July 2023

Membrane manufacturing system was operated using dry/wet phase inversion process. A sample of hollow fiber membrane was prepared using (17% wt PVC) polyvinyl chloride as membrane material and N, N Dimethylacetamide (DMAC) as solvent in the first run and the second run was made using (DMAC/Acetone) of ratio 3.4 w/w. Scanning electron microscope (SEM) was used to predict the structure and dimensions of hollow fiber membranes prepared. The ultrafiltration experiments were performed using soluble polymeric solute poly ethylene glycol (PEG) of molecular weight (20000 Dalton) 800 ppm solution 25 °C temperature and 1 bar pressure. The experimental results show that pure water permeation increased from 25.7 to 32.2 (L/m2.h.bar) by adding acetone to the dope solution, while rejection decreased from 91.8 to 63.2%.
Microsurgical management of midbrain gliomas: surgical results and long-term outcome in a large, single-surgeon, consecutive series
Authors: Serra Carlo , Türe Hatice , Fırat Zeynep , Staartjes Victor E. , Yaltırık Cumhur Kaan , Ekinci Gazanfer , Sav Aydin , Türe Uğur
Published: July 2023

OBJECTIVE

The authors report on a large, consecutive, single-surgeon series of patients undergoing microsurgical removal of midbrain gliomas. Emphasis is put on surgical indications, technique, and results as well as long-term oncological follow-up.

METHODS

A retrospective analysis was performed of prospectively collected data from a consecutive series of patients undergoing microneurosurgery for midbrain gliomas from March 2006 through June 2022 at the authors’ institution. According to the growth pattern and location of the lesion in the midbrain (tegmentum, central mesencephalic structures, and tectum), one of the following approaches was chosen: transsylvian (TS), extreme anterior interhemispheric transcallosal (eAIT), posterior interhemispheric transtentorial subsplenial (PITS), paramedian supracerebellar transtentorial (PST), perimedian supracerebellar (PeS), perimedian contralateral supracerebellar (PeCS), and transuvulotonsillar fissure (TUTF). Clinical and radiological data were gathered according to a standard protocol and reported according to common descriptive statistics. The main outcomes were rate of gross-total resection; extent of resection; occurrence of any complications; variation in Karnofsky Performance Status score at discharge, 3 months, and last follow-up; progression-free survival (PFS); and overall survival (OS).

RESULTS

Fifty-four patients (28 of them pediatric) met the inclusion criteria (6 with high-grade and 48 with low-grade gliomas [LGGs]). Twenty-two tumors were in the tegmentum, 7 in the central mesencephalic structures, and 25 in the tectum. In no instance did the glioma originate in the cerebral peduncle. TS was performed in 2 patients, eAIT in 6, PITS in 23, PST in 16, PeS in 4, PeCS in 1, and TUTF in 2 patients. Gross-total resection was achieved in 39 patients (72%). The average extent of resection was 98.0% (median 100%, range 82%–100%). There were no deaths due to surgery. Nine patients experienced transient and 2 patients experienced permanent new neurological deficits. At a mean follow-up of 72 months (median 62, range 3–193 months), 49 of the 54 patients were still alive. All patients with LGGs (48/54) were alive with no decrease in their KPS score, whereas 42 showed improvement compared with their preoperative status.

CONCLUSIONS

Microneurosurgical removal of midbrain gliomas is feasible with good surgical results and long-term clinical outcomes, particularly in patients with LGGs. As such, microneurosurgery should be considered as the first therapeutic option. Adequate microsurgical technique and anesthesiological management, along with an accurate preoperative understanding of the tumor’s exact topographic origin and growth pattern, is crucial for a good surgical outcome.
The learning curve for cavernous sinus surgery illustrated by symptomatic intracavernous aneurysm clipping through a pretemporal transcavernous approach
Authors: Liao Chih-Hsiang , Lin Chun-Fu , Wang Jui-To , Wang Wei-Hsin , Chen Shao-Ching , Hsu Sanford P. C.
Published: July 2023

OBJECTIVE

The anatomy of the cavernous sinus (CS) has been well studied in the laboratory for decades; however, performing surgery in and around the CS is still a challenge. To reveal the learning curve for CS surgery via the pretemporal transcavernous approach (PTTC), surgical procedures were examined. The authors proposed 4 levels of surgical difficulty in opening the walls of the CS through this approach. Details of the approach were illustrated by surgical videos of symptomatic intracavernous aneurysm clipping.

METHODS

Four levels of surgical difficulty were proposed. The higher the level, the more the CS walls were opened. Pathologies corresponding to each level of difficulty in and around the CS were categorized in each level together with explanations. From 2015 to 2021, 5 patients with symptomatic intracavernous aneurysms (diplopia due to compressive cranial neuropathy) underwent the PTTC at the authors’ institute and served as representative cases in opening the walls of the CS. All CS cases from 2009 to 2021 were reviewed and categorized to demonstrate the learning curve.

RESULTS

Four levels of surgical difficulty are as follows: level 1, a basic Dolenc extradural approach, which involves opening the anterior third of the superior and lateral walls of the CS; level 2, mobilizing the internal carotid artery (ICA) and opening the proximal dural ring to enter the roof of the CS and treat lesions around the clinoid and upper cavernous ICA; level 3, opening the entire aspect of the superior and lateral walls of the CS, which involves opening the oculomotor triangle and peeling the lateral wall of the CS to the tentorial incisura; and level 4, mobilizing cranial nerves III, IV, and V1 to gain access to the supra-/infratrochlear triangles to have proximal ICA control and opening the posterior wall as the last step to enter the posterior fossa. Surgical steps were described and illustrated with surgical videos of symptomatic intracavernous aneurysm clipping.

CONCLUSIONS

The learning curve for CS surgery is long. The authors use 4 levels of surgical difficulty to describe applications of the PTTC in CS surgery. This approach serves as an effective workhorse in treating CS pathologies with low morbidity and high success rates when performed by experienced neurosurgeons.
Clinical outcomes and proximal junctional failure in adult spinal deformity patients corrected to normative alignment versus functional alignment
Authors: Protopsaltis Themistocles S. , Ani Fares , Soroceanu Alexandra , Lafage Renaud , Kim Han Jo , Balouch Eaman , Norris Zoe , Smith Justin S. , Daniels Alan H. , Klineberg Eric O. , Ames Christopher P. , Hart Robert , Bess Shay , Shaffrey Christopher I. , Schwab Frank J. , Lenke Lawrence G. , Lafage Virginie , Gupta Munish C.
Published: July 2023

OBJECTIVE

The objective of this study was to explore the rate of proximal junctional failure (PJF) and functional outcomes of normative alignment goals compared with alignment targets based on age-appropriate physical function.

METHODS

Baseline relationships between age, pelvic incidence (PI), and a component of the T1 pelvic angle (TPA) within the fusion were analyzed in adult spinal deformity (ASD) patients and compared with those of asymptomatic patients. Linear regression modeling was used to determine alignment based on PI and age in asymptomatic patients (normative alignment), and in ASD patients, alignment corresponding to age-appropriate functional status (functional alignment). A cohort of 288 ASD patients was split into two groups based on whether the patient was closer to their normative or functional alignment goal at their 6-week postoperative radiographic follow-up. The rates of proximal junctional kyphosis (PJK) and PJF were determined for each cohort.

RESULTS

In the 288 ASD patients included in this pre- to postoperative analysis, there was no difference in baseline alignment or health-related quality of life (HRQOL) between the normative alignment and functional alignment groups. At 6 weeks, patients with normative alignment had a smaller TPA (4.45° vs 14.1°) and PI minus lumbar lordosis (−7.24° vs 7.4°) (both p < 0.0001) and higher PJK (40% vs 27.2%, p = 0.03) and PJF (17% vs 6.8%, p = 0.008) rates than patients with functional alignment.

CONCLUSIONS

Correction in ASD patients to normative alignment resulted in higher rates of PJK and PJF without improvements in HRQOL. Correction in ASD patients to functional alignment that mirrors the physical function of their age-matched asymptomatic peers is recommended.
Retrospective single-surgeon study of prone versus lateral robotic pedicle screw placement: a CT-based assessment of accuracy
Authors: Brown Nolan J. , Pennington Zach , Kuo Cathleen C. , Shahrestani Shane , Gold Justin , Diaz-Aguilar Luis D. , Mehkri Yusuf , Singh Rohin , Gendreau Julian , Pham Martin H.
Published: July 2023

OBJECTIVE

Lateral lumbar interbody fusion including anterior-to-psoas oblique lumbar interbody fusion has conventionally relied on pedicle screw placement (PSP) for construct stabilization. Single-position surgery with lumbar interbody fusion in the lateral decubitus position with concomitant PSP has been associated with increased operative efficiency. What remains unclear is the accuracy of PSP with robotic guidance when compared with the more familiar prone patient positioning. The present study aimed to compare robot-assisted screw placement accuracy between patients with instrumentation placed in the prone and lateral positions.

METHODS

The authors identified all consecutive patients treated with interbody fusion and PSP in the prone or lateral position by a single surgeon between January 2019 and October 2022. All pedicle screws placed were analyzed using CT scans to determine appropriate positioning according to the Gertzbein-Robbins classification grading system (grade C or worse was considered as a radiographically significant breach). Multivariate logistic regression models were constructed to identify risk factors for the occurrence of a radiographically significant breach.

RESULTS

Eighty-nine consecutive patients (690 screws) were included, of whom 46 (477 screws) were treated in the prone position and 43 (213 screws) in the lateral decubitus position. There were fewer breaches in the prone (n = 13, 2.7%) than the lateral decubitus (n = 15, 7.0%) group (p = 0.012). Nine (1.9%) radiographically significant breaches occurred in the prone group compared with 10 (4.7%) in the lateral decubitus group (p = 0.019), for a prone versus lateral decubitus PSP accuracy rate of 98.1% versus 95.3%. There were no significant differences in BMI between prone versus lateral decubitus cohorts (30.1 vs 29.6) or patients with screw breach versus those without (31.2 vs 29.5). In multivariate models, the prone position was the only significant protective factor for screw accuracy; no other significant risk factors for screw breach were identified.

CONCLUSIONS

The present data suggest that pedicle screws placed with robotic assistance have higher placement accuracy in the prone position. Further studies will be needed to validate the accuracy of PSP in the lateral position as single-position surgery becomes more commonplace in the treatment of spinal disorders.
Proximal forearm nerve branching patterns: an anatomical study and its clinical significance
Authors: Zancolli Pablo , Johnston Benjamin R. , Martinez Ezequiel F. , Brown Justin M.
Published: July 2023

OBJECTIVE

The aim of this study was to add to the understanding of nerve branching patterns in the proximal forearm and consider optimal nerve transfer options to address the various injuries that affect the function of the upper extremity.

METHODS

Eleven upper-extremity cadaveric specimens were dissected to expose the radial, median, and ulnar nerves in the proximal forearm. The site of origin of nerve branches from the major nerves was assessed, with measurements made in reference to the lateral epicondyle for the radial nerve branches and the medial epicondyle for the median and ulnar nerve branches. The distances to where these branches entered their respective muscles (muscle entry point) were assessed using the same landmarks. To plan a transfer, the length of the nerve branches was then calculated as the difference from the apparent origin from the main nerve trunk to the location where the nerve entered the muscle. Importantly, the nerve branch origin was established as the location of obvious separation from the main nerve trunk without additional fascicular dissection from the major nerve trunk. The number of branches was determined, and the diameter for each branch was measured using a Vernier caliper.

RESULTS

The radial nerve branch to the extensor carpi radialis brevis (ECRB) muscle had an average length of 50.7 mm and average diameter of 1.6 mm. The mean medial and lateral lengths of the radial branches to the supinator muscle were found to be 22.2 mm (diameter 1.4 mm) and 15.3 mm (diameter 1.3 mm), respectively. The anterior interosseous nerve (AIN) branch of the median nerve was found 67.8 mm distal to the medial epicondyle with a diameter of 2.3 mm. The flexor carpi ulnaris (FCU) muscle innervation from the ulnar nerve was provided by 3 or 4 branches in most specimens. The second and third of these branches were the longest, with means of 30.5 mm (diameter 1.4 mm) and 30.7 mm (diameter 1.3 mm), respectively.

CONCLUSIONS

While there is variability of the nerve branching pattern in the proximal forearm between specimens, the authors provide evidence of commonalities (branching patterns and distances) that can facilitate planning for upper-extremity nerve reconstructions. Importantly, all measurements are provided with reference to easily identified bony landmarks and to their muscle entry points to aid operative decision-making. These data complement the growing practice of nerve transfers in the upper extremity for a variety of pathologies.
The lumbar adjacent-level syndrome: analysis of clinical, radiological, and surgical parameters in a large single-center series
Authors: Cannizzaro Delia , Anania Carla D. , De Robertis Mario , Pizzi Andrea , Gionso Matteo , Ballabio Chiara , Ubezio Maria Cleofe , Frigerio Gian Marco , Battaglia Massimiliano , Morenghi Emanuela , Capo Gabriele , Milani Davide , Attuati Luca , Tomei Massimo , Riva Marco , Costa Francesco , Galbusera Fabio , Politi Letterio S. , Ortolina Alessandro , Fornari Maurizio
Published: July 2023

OBJECTIVE

The development of specific clinical and neurological symptoms and radiological degeneration affecting the segment adjacent to a spinal arthrodesis comprise the framework of adjacent-level syndrome. Through the analysis of a large surgical series, this study aimed to identify possible demographic, clinical, radiological, and surgical risk factors involved in the development of adjacent-level syndrome.

METHODS

A single-center retrospective analysis of adult patients undergoing lumbar fusion procedures between January 2014 and December 2018 was performed. Clinical, demographic, radiological, and surgical data were collected. Patients who underwent surgery for adjacent-segment disease (ASD) were classified as the ASD group. All patients were evaluated 1 month after the surgical procedure clinically and radiologically (with lumbar radiographs) and 3 months afterward with CT scans. The last follow-up was performed by telephone interview. The median follow-up for patients included in the analysis was 67.2 months (range 39–98 months).

RESULTS

A total of 902 patients were included in this study. Forty-nine (5.4%) patients required reoperation for ASD. A significantly higher BMI value was observed in the ASD group (p < 0.001). Microdiscectomy and microdecompression procedures performed at the upper or lower level of an arthrodesis without fusion extension have a statistically significant impact on the development of ASD (p = 0.001). Postoperative pelvic tilt in the ASD group was higher than in the non-ASD group. Numeric rating scale, Core Outcome Measures Index, and Oswestry Disability Index scores at the last follow-up were significantly higher in patients in the ASD group and in patients younger than 65 years.

CONCLUSIONS

Identifying risk factors for the development of adjacent-level syndrome allows the implementation of a prevention strategy in patients undergoing lumbar arthrodesis surgery. Age older than 65 years, high BMI, preexisting disc degeneration at the adjacent level, and high postoperative pelvic tilt are the most relevant factors. In addition, patients older than 65 years achieve higher levels of clinical improvement and postsurgical satisfaction than do younger patients.
Effect of workers’ compensation status on pain, disability, quality of life, and return to work after anterior cervical discectomy and fusion: a 1-year propensity score–matched analysis
Authors: Hani Ummey , Monk Steve H. , Pfortmiller Deborah , Stanley Gerry , Kim Paul K. , Bohl Michael A. , Holland Christopher M. , McGirt Matthew J.
Published: July 2023

OBJECTIVE

Patients with workers’ compensation (WC) claims are reported to demonstrate poorer surgical outcomes after lumbar spine surgery. However, outcomes after anterior cervical discectomy and fusion (ACDF) in WC patients remain debatable. The authors aimed to compare outcomes between a propensity score–matched population of WC and non-WC patients who underwent ACDF.

METHODS

Patients who underwent 1- to 4-level ACDF were retrospectively reviewed from the prospectively maintained Quality Outcomes Database (QOD). After propensity score matching, 1-year patient satisfaction, physical disability (Neck Disability Index [NDI]), pain (visual analog scale [VAS]), EQ-5D, and return to work were compared between WC and non-WC cohorts.

RESULTS

A total of 9957 patients were included (9610 non-WC and 347 WC patients). Patients in the WC cohort were significantly younger (50 ± 9.1 vs 56 ± 11.4 years, p < 0.001), less educated, and were more frequently male, non-Caucasian, and active smokers (29.1% vs 18.1%, p < 0.001), with greater baseline VAS and NDI scores and poorer quality of life (p < 0.001). One-year postoperative improvements in VAS, NDI, EQ-5D, and return-to-work rates and satisfaction were all significantly worse for WC compared with non-WC patients. After adjusting for baseline differences via propensity score matching, WC versus non-WC patients continued to demonstrate worse 3- and 12-month VAS neck pain and NDI (p = 0.010), satisfaction (χ2 = 4.03, p = 0.045), and delayed return to work (9.3 vs 5.7 weeks, p < 0.001).

CONCLUSIONS

WC status was associated with greater 1-year residual disability and axial pain along with delayed return to work, without any difference in quality of life despite having fewer comorbidities and being a younger population. Further studies are needed to determine the societal impact that WC claims have on healthcare delivery in the setting of ACDF.
Numerical Simulation of Highly Efficient Cs2TiI6 based Pb Free Perovskites Solar Cell with the Help of Optimized ETL and HTL Using SCAPS-1D Software
Authors: Halim Md Abdul , Islam Md. Shafiqul , Hossain Md. Momin , Ali Khan Md. Yakub
Published: July 2023

In order to provide the best photovoltaic application, this paper examines the physical, optical, and electrical aspects of Cesium Titanium (IV) based single halide Perovskite absorption materials. Perovskite solar cell for scavenging renewable energy, has grown more and more necessary in the context of the diversification of the use of natural resources. Due to its efficient band gap of 1.8 eV, Cs2TiI6 has become a desirable contender for today's thin-film solar cell. This article shows the spectrum responses of a planar Au/FTO/C60/Cs2TiI6/CH3NH3SnI3/Al based structure where CH3NH3SnI3 is used as a Hole transport layer (HTL) and C60 and FTO are utilized as Electron transport layers (ETL) under 300K temperature conditions. This research demonstrates that employing FTO and C60 as Electron transport layer charge extraction can be achieved. FTO provides High transmission, strong conductivity, and good adherence for the deposited layers. When used in a coevaporated perovskite solar cell, a C60 layer with an ideal thickness less than 15 nm improves charge extraction. This article tried to avoid cadmium for solar cell generation due to its toxicity on environment. The simulation included detailed configuration optimization for the thickness of the absorber layer, HTL, ETL, defect density, Wavelength, temperature, and series resistance.  In this work the Power Conversion Efficiency (η), Fill Factor (FF), Open-circuit Voltage (Voc), J-V Curve, Quantum Efficiency and Short-circuit current (Jsc) have been measured by varying thickness of absorber layer in the range of 1µm to 6 µm. The optimized perovskite solar cell shows a power conversion efficiency of 21.8429% when the absorber layer thickness is 4µm and electron transport layer thickness is 0.6µm.
Problems faced by hotel businesses within the scope of environmental analysis factors: The case of Akçakoca
Authors: MESCİ Muammer , ÇÖMLEKÇİ İstemi , ÖZTÜRK Emrah , BATMAN Orhan
Published: July 2023

The aim of the research is to identify the problems faced by hotel businesses within the scope of internal and external environmental factors. In this context, qualitative research method was applied in the research. Data was collected through face-to-face semi-structured interviews with people who are the owners and senior managers of hotel businesses operating in Akçakoca. A total of 10 hotel businesses were interviewed. Data were analyzed with descriptive analysis technique. As a result of the research, it has been revealed that the enterprises face economic, political, legal and natural environmental problems arising from the remote environmental factors. It was also found out that they do not generally encounter problems arising from immediate environmental factors. Lastly, it was found out that generally they face marketing, human resources, finance and accounting problems in general in the context of internal environmental factors.
Pengaruh Lingkungan Kerja Dan Iklim Organisasi Terhadap Kepuasan Kerja Dengan Komitmen Organisasi Sebagai Variabel Intervening Pada PT. Bank Pembangunan Daerah Sumatera Barat (Studi Kasus Kantor Bank Bpd Kantor Cabang KC. Siteba)
Authors: Widya Agustin Jennifer , Dwi Anggraini Meri , Chandrayanti Teti
Published: July 2023

Abstract: This study aims to examine and analyze the effect of work environment and organizational climate on job satisfaction with organizational commitment as a variable that intervenes partially or simultaneously. The population is 48 people and the sample is 48 people. Results of research 1). The work environment has no significant effect on organizational commitment at Bank BPD Offices KC Branch Offices. Siteba, 2). Organizational climate has a significant effect on organizational commitment at Bank BPD Offices KC Branch Offices. Siteba, 3). The work environment has a significant effect on job satisfaction at the Bank BPD Office KC Branch Office. Siteba, 4). Organizational climate has no significant effect on job satisfaction at Bank BPD Offices KC Branch Offices. Siteba, 5). Work environment has a significant effect on job satisfaction with organizational commitment as an intervention variable at the Bank BPD Office KC Branch Office. Siteba, 6). Organizational climate has a significant effect on job satisfaction with organizational commitment as an intervention variable at Bank BPD Offices KC Branch Offices. Siteba) and 7). Organizational commitment has no significant effect on job satisfaction at Bank BPD Offices KC Branch Offices. Site ba.

Abstrak: Penelitian ini bertujuan untuk menguji dan menganalisis pengaruh lingkungan kerja dan iklim organisasi terhadap kepuasan kerja dengan komitmen organisasi sebagai variabel intervening secara parsial maupun simultan Populasi 48 orang dan sampel 48 orang. Hasil dari penelitian 1). Lingkungan kerja tidak berpengaruh signifikan terhadap komitmen organisasi pada Kantor Bank BPD Kantor Cabang KC. Siteba, 2). Iklim organisasi berpengaruh signifikan terhadap komitmen organisasi pada Kantor Bank BPD Kantor Cabang KC. Siteba, 3). Lingkungan kerja berpengaruh signifikan terhadap kepuasan kerja pada Kantor Bank BPD Kantor Cabang KC. Siteba, 4). Iklim organisasi tidak berpengaruh signifikan terhadap kepuasan kerja pada Kantor Bank BPD Kantor Cabang KC. Siteba, 5). Lingkungan kerja berpengaruh signifikan terhadap kepuasan kerja dengan komitmen organisasi sebagai variabel intervening pada Kantor Bank BPD Kantor Cabang KC. Siteba, 6). Iklim organisasi berpengaruh signifikan terhadap kepuasan kerja dengan  komitmen organisasi sebagai variabel intervening pada Kantor Bank BPD Kantor Cabang KC. Siteba) dan 7). Komitmen organisasi tidak berpengaruh signifikan terhadap kepuasan kerja pada Kantor Bank BPD Kantor Cabang KC. Siteba.
Pengaruh Lingkungan Kerja Dan Iklim Organisasi Terhadap Kepuasan Kerja Dengan Komitmen Organisasi Sebagai Variabel Intervening Pada PT. Bank Pembangunan Daerah Sumatera Barat (Studi Kasus Kantor Bank Bpd Kantor Cabang KC. Siteba)
Authors: Musliana Nada , Hadya Riska
Published: July 2023

Abstract: This study aims to examine and analyze 1) the influence of HR information systems on the human resource input function on employee performance at PT. Bima Arjuna Prakasa. 2) the effect of the HR information system output function on employee performance at PT. Bima Arjuna Prakasa. 3) the influence of the input function of the HR information system and the output function of the HR information system on employee performance at PT. Bima Arjuna Prakasa. The population is 30 people and the sample is 30 people. The method of data analysis is Multiple Linear Regression Analysis and the coefficient of determinant, while the method of testing the hypothesis is the t test and F test. The results show 1. Partially the input function variable of the HR Information System has a positive and significant effect on the performance of employees of PT Bima Arjuna Prakasa Padang City, 2. Partially the output function variable of the HR Information System has a positive and significant effect on employee performance at PT Bima Arjuna Prakasa Padang City, 3. The input function variables of the HR Information System and the output function of the HR Information System simultaneously or simultaneously have a significant and significant effect on performance employee. at PT. not examined in this study. 

Abstrak: Penelitian ini bertujuan untuk menguji dan menganalisis 1) pengaruh sistem informasi SDM pada fungsi input sumber daya manusia terhadap kinerja karyawan pada PT. Bima Arjuna Prakasa. 2) pengaruh fungsi output sistem informasi SDM terhadap kinerja karyawan pada PT. Bima Arjuna Prakasa. 3) pengaruh fungsi input sistem informasi SDM dan SDM fungsi keluaran sistem informasi terhadap kinerja karyawan pada PT. Bima Arjuna Prakasa. Populasinya 30 orang dan sampelnya 30 orang. Metode analisis data adalah Analisis Regresi Linier Berganda dan koefisien determinan, sedangkan metode pengujian hipotesis adalah uji t dan uji F. Hasil penelitian menunjukkan 1. Secara parsial variabel fungsi input Sistem Informasi SDM berpengaruh positif dan signifikan terhadap kinerja karyawan PT Bima Arjuna Prakasa Kota Padang, 2. Secara parsial variabel fungsi output Sistem Informasi SDM berpengaruh positif dan berpengaruh signifikan terhadap kinerja karyawan pada PT Bima Arjuna Prakasa Kota Padang, 3. Variabel fungsi input Sistem Informasi SDM dan fungsi output Sistem Informasi SDM secara simultan atau simultan berpengaruh signifikan dan signifikan terhadap kinerja karyawan. di PT Bima Arjuna Prakasa di kota Padang, 4. Kontribusi pengaruh fungsi input Sistem Informasi SDM dan fungsi output Sistem Informasi SDM terhadap kinerja karyawan PT Bima Arjuna Prakasa di Kota Padang sebesar 68,7% sedangkan sisanya 31,3% dipengaruhi oleh variabel lain yang tidak diteliti dalam penelitian ini.