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This study aimed to investigate the hydrodesulfurization (HDS) of a mixture of crude oil fractions (e.g., naphtha, kerosene, and gas oil) all in one time in a single reactor under various operating parameters such as temperature (T = 310–370 °C), pressure (P = 40–55 bar), weight hour space velocity (WHSV = 1.2–3.6 h−1), hydrogen-to- hydrocarbon ratio (150–300 vol/vol), and type of catalysts (di-metallic and tri-metallic). Experimental results showed that temperature and pressure have positive effects on process performance while weight hour space velocity gives a different trend. Results indicated that HDS efficiency was 95.8% at optimized operating parameters T = 350 °C, P = 50 bars, WHSV = 1.2 h−1, and (H2/HC) ratio = 200 vol/vol. and with NiCoMo/γ-Al2O3 catalyst which offered a higher HDS efficiency compared with other types of catalysts used. Kinetic analysis revealed that a pseudo-first order rate law is well expressing the HDS reaction of the operating system for all types of catalysts. Estimation of rate parameters over each type of catalyst was also presented. Study of mass transfer limitations revealed that surface reaction is the rate controlling step. Feasibility of the proposed technique may offer a large reduction in fixed and operating costs of the HDS unit in a modern petroleum refinery. Keywords: Hydrotreatment, Crude oil fractions, Sulfur removal, Catalytic reactor, Kinetic analysis, Di-metallic catalyst, Tri-metallic catalyst

In recent decades, conducting polymers (CPs) like polyaniline and polypyrrole have attracted the attentions of scientists all over the world due to having important advantages such as simplicity of synthesis, excellent chemical/mechanical stability and good optical properties. Despite the existence of different shortcomings in the pristine form of CPs, hybridization with other substances can be a great solution to decrease these limitations. The synergetic influences of CPs with composites can make them a promising option for industrial-based applications in electronics, medical, biomedical and optoelectronic fields. This paper aims to present a comprehensive review for expert and non-expert readers to be acquainted with the recent advancements in the field of perception, characterization and synthesis of different types of CPs in industries. Additionally, this paper overviews the application of commonly-applied CPs in industrial activities and present the advantages/disadvantages of each of them to provide an opportunity for readers to know the efficiency and feasibility of using each CP based on their conductivity and other related parameters.

In the present study, TiFe2O4@SiO2–SO3H heterogeneous catalyst was successfully synthesized and applied to generate biodiesel from oleic acid, and palmitic acid using an esterification process. In this sense, the nanocatalyst surface was characterized using TEM, TGA, XRD, FTIR, VSM, BET, SEM, and EDX analyses. Nanocatalyst TiFe2O4@SiO2–SO3H showed high activity for the esterification of oleic acid and palmitic acid. Also, the nanocatalyst can be easily recovered with a bar magnet and reused many times without any loss of activity.

This paper reports the synthesis of a new heterocyclic compound, 2,7-dicloropyrido[2,3-g]quinoline-3,8-dicarbaldehyde, from p-phenylene diamine by converting p-acetanilide (1) and reacting with Vilsmeier-Haack reagent (2). Chalcone(3) is produced when two moles of 2-acetyl naphthalene respond with the two carbaldehydes in compound (2). This chalcone serves as a reagent for quantifying amino group-containing pharmaceutical compounds. At the same time, a sensitive spectrophotometric technique has been created and used in pharmaceutical preparations to measure cefotaxime sodium by diazotizing and coupling with chalcone reagent. The recommended method diazotizes the medicinal molecule with sodium nitrite in an acidic solution to form the diazonium salt. This salt is combined with Chalcone reagent in an essential medium to create a stable and colorful azo dye soluble in water. Maximum absorption of the product is shown at 406 nm. Throughout the concentration range of 0.5–30 µg/ml, Beer's law was followed. The M absorptivity was (18381.44) liters mol-1. cm-1, the average recovery rate was 100.48 percent, and the relative standard deviation was less than 0.9 %. Injection-ready pharmaceutical preparations were the focus of the methodology.

Background: Appropriate surgical infrastructure is important for improving patient outcomes. However, low- and middle-income countries (LMICs) often struggle to provide adequate brain tumor surgery due to fractured infrastructure. This study aims to identify and evaluate the barriers to surgical care infrastructure for brain tumors in LMICs., Method: A comprehensive literature search was conducted from inception to October 20, 2022, using PubMed, Scopus, CINAHL, and Google Scholar. Inclusion criteria were studies that focused on the surgical care of brain tumors in terms of infrastructure in low-resource settings. Studies were excluded if they did not focus on surgical care or were not conducted in LMIC. Data was extracted and analyzed qualitatively., Results: A final analysis of 39 studies showed significant barriers: 66% had poor operating room infrastructure, 32% lacked specialized care centers and imaging facilities, 26% faced long-distance travel issues, 13% had poor public health infrastructure, and 11% had poor referral pathways and lacked advanced diagnostic facilities. Additionally, 3% had an uneven distribution of quality centers and inadequate ward capacity. Proposed strategies include cross-border collaboration (29%), optimizing existing resources (29%), improving referral pathways (7%), resource sharing within hospitals, and acquiring surgical devices through donations (7%)., Conclusion: The review highlights key barriers in infrastructure while providing effective neurosurgical care to brain tumors in LMICs. To overcome these challenges, targeted strategies need to be implemented by stakeholders, policymakers, and health ministries., (Copyright © 2024. Published by Elsevier Inc.)

Objective: To compare outcomes of middle meningeal artery embolization (MMAE) alone versus combined with conventional surgery in the management of chronic subdural hematoma (cSDH)., Methods: A systematic literature search was performed on PubMed, Google Scholar, Scopus, and CINAHL, followed by a meta-analysis comparing recurrence rates, surgical rescue, mortality, in-hospital complications, and length of hospital stay was conducted. Mean differences and risk ratios were pooled using a random effects model, with subgroup analysis performed using Cochrane RevMan 5.4.1 software., Results: A total of 23 studies including 302,168 patients (62.5 % male, 37.5 % female) were analyzed, with most studies published between 2017 and 2024. Among these patients, 299,195 (99.0 %) were treated with conventional surgery, whereas 3113 underwent MMAE. MMAE patients showed a significantly lower recurrence rate compared to conventional surgery, with a 0.35 times lower risk of recurrence (95 % CI: 0.24-0.51, p<0.01). However, adjunctive MMAE was associated with a longer hospital stay (SMD: 2.61 [95 % CI: 2.46-2.76], p<0.01), though MMAE alone had a shorter stay compared to adjunctive MMAE. Additionally, MMAE demonstrated a lower risk of surgical rescue (0.29 times, p<0.01). While no significant difference was found in-hospital complications (RR: 1.01, 95 % CI 0.90-1.14, p=0.84) and mortality rates (RR: 0.88, 95 % CI 0.69-1.14, p=0.34)., Conclusion: MMAE stand-alone or adjunctive with conventional surgery presents a promising alternative to conventional surgery alone for chronic subdural hematomas due to lower recurrence and surgical rescue risk. Further prospective studies are needed to study the efficacy of this new approach., (Copyright © 2024. Published by Elsevier B.V.)

Objective: To evaluate the role of endovascular thrombectomy (EVT) in patients presenting with acute ischemic stroke (AIS) due to large vessel occlusion in the very late window (>24 hours)., Methods: A systematic review was conducted according to PRISMA guidelines using PubMed, CINAHL, Scopus, and Google Scholar databases till 2024. Quality assessment was performed using the Newcastle-Ottawa Scale (NOS). Outcomes were analyzed with a single-arm meta-analysis (Sidik-Jonkman model) and a double-arm meta-analysis (Mantel-Haenszel model) to compare EVT within and after 24 hours, reporting pooled risk ratios. Analysis was performed using STATA version 18.0 and Review Manager version 5.4.1, with p<0.05 considered significant., Results: This review included 35 studies with 15,086 patients. The proportion of symptomatic intracerebral hemorrhage (sICH) in patients treated with EVT after 24 hours was 4.78 % (95 % CI: 3.20 %-6.58 %), with a risk ratio (RR) of 0.85 (95 % CI: 0.44-1.64) compared to EVT patients treated within 24 hours. The pooled percentage for functional independence (90 day mRS 0-2) was 35.73 % (95 % CI- 27.26 %, 44.64 %) with a risk ratio of 0.85 (95 % CI: 0.34, 2.09). The proportion of the 90-day mortality was 22.30 % (95 % CI: 16.12 %, 29.09 %), with a risk ratio of 1.08 (95 % CI: 0.73, 1.61). The overall proportion of intracerebral hemorrhage (ICH) was 12.23 % (95 % CI: 5.47-20.86) following EVT after 24 hours., Conclusion: Patients treated with EVT after 24 hours have comparable safety and effectiveness to those treated within 24 hours. The outcomes suggest that EVT after 24 hours is a viable treatment option, offering similar benefits to earlier intervention., (Copyright © 2024. Published by Elsevier B.V.)

In our research we explore the world of PACDs, carbon dots synthesized from pamoic acid through a single step pyrolysis method. Our findings reveal that PACDs have capabilities of serving as sensitive and selective sensors in both colorimetric and fluorescent modes. They are particularly effective, at colorimetrically and fluorometrically detecting ferric ions and can also act as fluorometric sensors for pH. When ferric ions are introduced an interesting transformation occurs. A noticeable change in color unfolds before our eyes, under 365 nm UV light the fluorescence shifts from green to blue while in daylight it changes from a yellow to a deep ink blue. Notably these detection techniques can precisely measure ferric ions within concentrations ranging from 5 µM to 80 µM with a detection limit of 0.1 µM for fluorescence response. Additionally, they can detect ferric ions colorimetrically within the range of 5 µM to 45 µM with a detection limit of 3.8 µM. Furthermore, the PACDs exhibit a capability to adapt to different pH levels. In alkaline environments with a pH range between 8 and 11 the fluorescence signal demonstrates a response that directly correlates with pH levels and slightly shifts its position. In contrast under acidic conditions a noticeable shift, towards blue is observed in the fluorescence signal leading to a change in color from green to blue when exposed to UV light. This shift persists as the fluorescence signal directly correlates with decreasing pH levels in settings. Apart from their proficiency in ferric ion detection and pH monitoring, the PACDs also demonstrate potential in cancer research. Through an assessment using the MTT assay it was discovered that the PACDs exhibit cytotoxic effects against five different cancer cell lines; HCT 116, MDA MB 231, Hep3B, MCF 7 and HeLa. The findings are promising as the PACDs show IC50 values of 12.5 µg/ml 6.25 µg/ml 25 µg/ml 50 µg/ml and 100 µg/ml for these cell lines. This research highlights the versatility and potential of PACDs as a tool, in both sensing applications and oncology research., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Low- and middle-income countries (LMICs) often struggle to provide adequate neurosurgical care due to poor governance and institutional efforts, making access to care difficult. Therefore, our review of literature aims to identify gaps in government, national, and institutional efforts to combat barriers to neurosurgical care of brain tumors in LMICs, to inform future policy and action planning., Methods: A comprehensive literature search was conducted using PubMed, Scopus, Google Scholar, and CINAHL without language restrictions from inception to October 20, 2022. After screening and data extraction, a thematic analysis based on the National Surgical, Obstetric, and Anesthesia Plan (NSOAP) systematically identified and classified notable themes, which were then quantified and presented as percentages., Results: A total of 12 studies were included in the final analysis. The review highlighted some of the barriers to providing surgical care of brain tumors in LMICs, including political instability (14%), inadequate national budget for health care (43%), poor government support (14%), lack of support of hospital management (14%), and no coverage under national insurance plans (14%). Strategies that can be implemented to address the barriers include strengthening the local health system (17%), advocating for health ministry support (33%), developing national treatment guidelines (17%), making neurosurgery a part of the national surgical plan (17%), fostering collaborations across various levels of government (17%), changing national insurance policy to include neurosurgical care (17%), and advocating for more resources and changes in global care (33%)., Conclusions: Effective governance plays a critical role in addressing challenges as it shapes the availability of resources and policies that affect the quality of care provided. Our study outlines key challenges and strategies reported within literature in an attempt to drive government attention and thereby policy to support the neurosurgical care of brain tumors, particularly in the developing world., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Health care in developing countries often lacks adequate bookkeeping and national cancer registries, means of information that have proven to impact disease research and care. The true burden of brain tumors therefore remains unchecked and so does the extent of the problem. Therefore, this study aims to explore the challenges and potential strategies related to information management of brain tumors in low- and middle-income countries (LMICs)., Methods: A comprehensive literature search conducted using databases such as PubMed, Scopus, Google Scholar, and Cumulated Index in Nursing and Allied Health Literature, without any language restrictions, from inception to October 20, 2022. Following screening and extraction of data, themes were generated using the information management domain of the National Surgical, Obstetric, and Anesthesia Plan framework., Results: The final analysis includes 23 studies that highlighted the challenges to managing information to the surgical care given to brain tumors in LMICs, including lack of proper hospital record system (43%), lack of national brain tumor registry (67%), lack of local management guidelines (10%), and low research output (33%). Some of the proposed strategies in the literature to address these barriers include improving data management systems (45%), developing a population-based brain tumor registry (64%), and formulating local treatment guidelines (9%) for the management of brain tumors., Conclusions: In LMICs, improving patient outcomes and quality of life postneurosurgical intervention for brain tumors requires coordinated efforts to enhance information systems. The support of the government and public health professionals is vital in implementing strategies to achieve this goal., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Conservative treatments for minimally symptomatic chronic subdural hematoma (cSDH) are debated, with surgery as the primary option., Objective: To assess failure rates of a conservative approach for management of cSDH., Methods: We searched PubMed, SCOPUS, Web of Science, and ClinicalTrials.gov for studies on conservative management of cSDH and analyzed the data using R (version 4.1.2)., Results: A total of 35 studies including 2095 patients were analyzed: 950 (45%) of the patients were in the observation group, 671 (32%) in the corticosteroid group, 355 (17%) in the atorvastatin group, 43 (2%) in the mannitol group, 52 (2.5%) in the tranexamic acid group, and 24 (1.1%) in the etizolam group. Our pooled analysis showed that 19.82% of patients required rescue surgery (95% confidence interval [CI]: 12.98% to 26.66%, P < 0.0001). The overall pooled risk ratio (RR) for the effect of interventions on the need for rescue surgery was 0.2424 (95% CI: 0.1577 to 0.3725, Iˆ2 = 90.5%, P < 0.0001). Subgroup analysis showed varied effects: observation group (RR = 0.3482, 95% CI: 0.1045 to 1.1609, Iˆ2 = 94.0%), corticosteroids (RR = 0.2988, 95% CI: 0.1671 to 0.5344, Iˆ2 = 90.8%), atorvastatin (RR = 0.1609, 95% CI: 0.0985 to 0.2627, Iˆ2 = 53.2%), mannitol (RR = 0.0370, 95% CI: 0.0009 to 1.5244), and tranexamic acid (RR = 0.0585, 95% CI: 0.0026 to 1.2924)., Conclusions: The rate of rescue surgery in conservatively managed cSDH patients remains high. Corticosteroids or atorvastatin demonstrates some potential benefit in reducing the failure rate but collective effectiveness is unknown., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Adjuvant therapy is an important tool in the arsenal of brain tumor management and can improve patients' outcomes significantly but low- and middle-income countries (LMICs) often face challenges in provision. Therefore, our study aims to highlight barriers and strategies to adjuvant therapy of brain tumors in low-resource settings., Method: A comprehensive search of literature was conducted using PubMed, CINAHL, Google Scholar, and Scopus, from inception to October 20, 2022. The review included studies on adjuvant therapy for brain tumors in LMICs and identified themes using the National Surgical, Obstetric, and Anesthesia Plan (NSOAP) domains., Results: 32 studies were included in the review. The most reported barriers to adjuvant care were limited access to healthcare (14 %), limited access to chemotherapy and radiation equipment (25 %), and traditional or alternative medications (11 %). Strategies for improvement include improving the availability of specialized radiation oncology training (8 %) and improving access to neuro-diagnostics and neurotherapeutics (12 %). In addition, efforts to subsidize treatment (4 %) and provide financial coverage through the Ministry of Health (4 %) can help to address the high cost of care and improve access to funding for chemotherapy. Finally, establishing documentation systems and registries (16 %), implementing standardized national treatment guidelines (8 %) can help to improve overall care for brain tumor patients in LMICs., Conclusion: A multimodal approach of strategies targeting workforce, infrastructure, service delivery, financing, and information management is needed to improve adjuvant care for brain tumors. International collaboration and partnerships can also play a key role in addressing barriers and improving care in LMICs., Competing Interests: Declaration of Competing Interest None., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Limited neurosurgical workforces remain one of the critical problems experienced in low resource settings. Therefore, our study aims to explore and summarize the key challenges to neurosurgical care of brain tumors in terms of workforce in LMICs. A comprehensive literature search was conducted using Scopus, PubMed, CINAHL, and Google Scholar from inception to October 20, 2022. All extracted data were screened independently by 2 reviewers and thematically analyzed. We found and screened 3764 articles, of which 33 studies were included in our final analysis as per our inclusion criteria. Among the studies included, 33% highlighted the limited number of neurosurgeons, 39% emphasized the absence of specialized surgical teams, 7% pointed out a shortage of nursing staff, and 4% noted suboptimal anesthesia teams. The study uncovered the need for improved training programs in neuro-oncology (32%) and neuro-anesthesia (3%), as well as improved collaboration (32%), and multidisciplinary team structures (15%), are essential for tackling these workforce challenges and improving patient outcomes. It is crucial to implement targeted interventions and policy changes to address the barriers to the workforce in providing effective neurosurgical care to patients with brain tumors in developing countries. This might entail capacity building and training programs for healthcare professionals. Policymakers should consider allocating resources and funding for workforce development and making neurosurgical care a priority in healthcare plans., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Making neurosurgical care accessible to a larger portion of the population in low- and middle-income countries (LMICs) is integral due to the high mortality and morbidity associated with brain tumors. However, the high cost of care often makes it financially out of reach for many individuals. Therefore, this review aims to identify barriers to neurosurgical care of brain tumors in terms of financing in LMICs., Methods: Without restriction to language, a search of the literature was undertaken in a number of databases, including PubMed, Scopus, Google Scholar, and CINAHL, in order to find the most pertinent research involving financing of brain tumors in LMICs. The last day of the search was October 20, 2022. Following screening and data extraction, significant themes were found and categorized using thematic analysis., Results: A total of 28 studies were analyzed in this review. The review highlighted some of the barriers to providing surgical care of brain tumors in LMICs. In the cited studies, surgical expenses (41%), neuroimaging costs (30%), and care-related expenses (33%) were the primary concerns. Addressing these challenges involves cross-border collaboration (23%), transparent financing systems (46%), awake craniotomy (15%), cost-effective/reusable intra-operative supplies (8%), and optimizing resources in healthcare systems (8%)., Conclusions: This study explored barriers and challenges to financing neurosurgical care of brain tumors in LMICs. Government support and transparency in healthcare financing should be prioritized to ensure that all individuals have access to surgical care of brain tumors., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: A meta-analysis was conducted to compare: 1) time from traumatic brain injury (TBI) to the hospital, and 2) time within the hospital to intervention or surgery, by country-level income, World Health Organization region, and healthcare payment system., Methods: A comprehensive literature search was conducted and followed by a meta-analysis comparing duration of delays (prehospital and intrahospital) in TBI management. Means and standard deviations were pooled using a random effects model and subgroup analysis was performed using R software., Results: Our analysis comprised 95,554 TBI patients from 45 countries., By Country-Level Income: From 23 low- and middle-income countries, a longer mean time from injury to surgery (862.53 minutes, confidence interval [CI]: 107.42-1617.63), prehospital (217.46 minutes, CI: -27.34-462.25), and intrahospital (166.36 minutes, 95% CI: 96.12-236.60) durations were found compared to 22 high-income countries., By Who Region: African Region had the greatest total (1062.3 minutes, CI: -1072.23-3196.62), prehospital (256.57 minutes [CI: -202.36-715.51]), and intrahospital durations (593.22 minutes, CI: -3546.45-4732.89)., By Healthcare Payment System: Multiple-Payer Health Systems had a greater prehospital duration (132.62 minutes, CI: 54.55-210.68) but greater intrahospital delays were found in Single-Payer Health Systems (309.37 minutes, CI: -21.95-640.69)., Conclusion: Our study concludes that TBI patients in low- and middle-income countries within African Region countries face prolonged delays in both prehospital and intrahospital management compared to high-income countries. Additionally, patients within Single-Payer Health System experienced prolonged intrahospital delays. An urgent need to address global disparities in neurotrauma care has been highlighted., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: While early diagnosis of brain tumors is essential for improving prognoses, several challenges prevent early diagnosis of these illnesses in low- and middle-income countries (LMICs). The objective of this systematic review is to identify and evaluate the barriers and challenges to early detection of brain tumors in LMICs, as well as to propose potential solutions., Methods: A thorough search of the literature was carried out with the aid of multiple databases, including Google Scholar, CINAHL, PubMed, and Scopus. Studies focusing on the early detection of brain tumors in low- and middle-income countries met the inclusion criteria for this review. Articles were screened independently by 2 reviewers. National Surgical, Obstetric, and Anesthesia plan framework was used to extract relevant data and develop themes. Microsoft Excel was then used to arrange and analyze these themes., Results: Out of 21 articles included in the final analysis, notable challenges to early detection of brain tumors included healthcare providers' lack of awareness of early signs and symptoms of brain tumors (21%), limited diagnostic facilities (38%), misdiagnosis by healthcare providers (33%), and financial constraints (46%). Potential strategies for addressing these barriers and challenges include educating healthcare providers on early warning signs (50%), improving the early referral system (25%) and establishing local clinical guidelines (19%)., Conclusions: Significant barriers to early detection persist in LMICs. Collaboration between stakeholders, legislators, health ministries, and governmental organizations is essential for developing and implementing focused interventions, such as establishment of referral pathways and specialized centers, adapting guidelines to local cultural contexts and raising public and professional awareness., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Introduction: Brain tumors pose a major challenge in low- and middle-income countries (LMICs) due to limited resources and high costs, resulting in hampered service delivery of neurosurgical care and significant disparities in patient outcomes compared to high-income nations. Therefore, our systematic review aims to identify barriers to service delivery in providing adequate surgical care for the management of brain tumors in LMICs., Methods: We searched Scopus, PubMed, Google Scholar, and CINAHL, from inception to October 20, 2022. The data from the eligible studies were extracted and analyzed qualitatively., Results: The final analysis included 35 articles, which highlighted significant challenges in providing adequate surgical care for brain tumors in LMICs. Among the cited studies, 10% reported lack of multidisciplinary team structures, 61% noted delayed patient presentation, 16% highlighted delays in neuroimaging, 10% reported delays in scheduling surgery, lack of training for specialized surgery (3%), lack of intra-operative facilities (19%), power supply interruption (6%), and lack of advanced diagnostic and specialized surgery facilities (19%). Strategies for addressing these challenges include cross-border collaboration (7%), public education, and awareness (13%), establishing multidisciplinary teams (20%), utilizing alternative surgical techniques (13%), 7% intraoperative ultrasound, 13% intraoperative cytology smear), and establishing satellite hospitals for low-risk care (7%), standard operating procedure and infection control (13%)., Conclusion: Targeted interventions considering economic constraints are essential to improve the availability, affordability, and quality of neuro-oncologic services in developing countries. International collaborations and building capacity are vital for improving patient outcomes and service delivery, as well as forming multidisciplinary teams and utilizing resource-saving, innovative methods., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Intraoperative brain smear is an easy, rapid, and cost-effective technique for immediate diagnosis of brain tumors. Earlier studies have gauged its application on limited number of samples, but its diagnostic accuracy especially in low-resource settings, where its practice would be extremely helpful, is still undetermined. To investigate the diagnostic accuracy of intraoperative brain smear in resource-limited settings for diagnosis of brain tumors., Methods: A systematic search was conducted on PubMed, Google Scholar, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Embase for all articles utilizing intraoperative brain smears that were extracted. Studies from low- and middle-income countries (LMICs) with test performance characteristics were selected and subsequent values were summarized using a hierarchical summary receiver operating characteristic (ROC) curve via STATA and pooled using a random-effects model on MetaDiSc 2.0., Results: Twelve studies consisting of 1124 patients were identified. Six studies included both adult and pediatric population groups, while 4 investigated adults and 2 included pediatric patients. The pooled diagnostic odds ratio (OR) was calculated to be 212.52 (CI: [104.27-433.13]) of Bivariable pooled specificity and sensitivity were 92% (CI: [86%-96%]) and 96% (CI: [93%-98%]), respectively., Conclusions: Our study shows that intraoperative brain smear is not only an accurate and sensitive diagnostic modality in resource-rich settings, but it is also equally useful in resource-limited settings, making it an ideal method for rapid diagnosis., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Despite 15,000 annual medical graduates, few choose neurosurgery, especially women. The scarcity of female neurosurgeons is a global concern, particularly in resource-limited settings such as Pakistan. This study focuses on gender-based differences in medical student perceptions of neurosurgery in Pakistan., Methods: A nationwide cross-sectional study was conducted from March 6 to April 20, 2023, using a Web-based survey. Data collectors were recruited through an ambassadorship program, distributed evenly across all provinces. A questionnaire was used after a pilot study. Data analysis was performed using SPSS version 26 and STATA 15., Results: A total of 2353 medical students participated in the study, of which 63.4% were female and 36.5% were male. Around 40.3% of women strongly agreed to the existence of potential gender bias in neurosurgery, in contrast to their corresponding male students, at 17.3%. Some of the highlighted deterring factors in pursuing neurosurgery as a career according to women include longer training duration (44.6%), poor work-life balance (41%), limited residency slots (50.6%), and limited exposure to neurosurgery (45.1%). Other factors included the high-intensity nature of training (33.6%), perceived gender bias (31.4%), competitive work environment (29.1%), complex surgical skills (38.6%), required level of medical knowledge (29.6%), and financial burden (33.9%)., Conclusions: Our study shows that female students are more likely to believe in the existence of potential gender bias in the field compared with their counterpart male participants, which highlights the graveness of the situation in view of the evident paucity of female neurosurgeons in the country., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Clinical research is necessary to evaluate neurosurgical interventions, yet clinical trials are conducted less frequently in low- and middle-income countries. Because specific barriers, facilitating factors, and strategies for neurosurgical clinical research in Uganda have not been previously identified, this study evaluated neurosurgical providers' perspectives on clinical research and documentation patterns of neurosurgical variables at Mulago National Referral Hospital., Methods: Retrospective review of 166 neurosurgical patient charts assessed the frequency of documentation of key variables. Twenty-two providers working in neurosurgery participated in 6 focus group discussions with qualitative analysis utilizing the framework method., Results: Chart review showed that primary diagnosis (99.4%), pupil light response (97.6%), and computed tomography scan results (93.3%) were documented for most patients. Cranial nerve exam (61.5%), pupil size (69.9%), and time to neurosurgical intervention (45%) were documented less frequently. On average, Glasgow Coma Scale was documented for 86.6% of days hospitalized, while vital signs were documented for 12.3%. In most focus group discussions, participants identified follow-up, financing, recruitment, time, approval, and sociocultural factors as research barriers. Participants described how the current health workforce facilitates successful research. To improve research capacity, suggested strategies focused on research networks, data collection, leadership, participant recruitment, infrastructure, and implementation., Conclusions: At Mulago National Referral Hospital, there was variability in the frequency of documentation of neurosurgical variables, which may impact data collection for future studies. While multiple barriers were identified, sociocultural, financing, and time barriers greatly impacted neurosurgical clinical research. Despite that, identified facilitating factors and strategies could be utilized to support neurosurgical research capacity growth., (Copyright © 2023. Published by Elsevier Inc.)

This is the first study that explored the potential use of Zizyphus mauritiana seed extract (ZSE) to synthesize nano-fluorohydroxyapatite/carboxymethyl chitosan nanocomposite scaffolds at different concentrations (CFZ1, CFZ2 and CFZ3) using co-precipitation method. The proposed scaffolds showed presence of intermolecular H bonding interactions between the constituents, according to the FTIR. The mechanical studies revealed shore hardness of 72 ± 4.6 and optimal compressive modulus in case of CFZ3 [1654.48 ± 1.6 MPa], that was comparable with that of human cortical bone. The SEM, TEM and platelet adhesion images corroborated uniformly distributed needle like particles in case of CFZ3 with an average size ranging from 22 to 26 nm, linked rough morphology, and appropriate hemocompatibility. The markedly up regulation in the ALP activity and protein adsorption upon increasing ZSE concentration demonstrated that CFZ nanocomposite scaffolds were compatible with osteoblastic cells relative to CF nanocomposite. The cytotoxicity study indicated that CFZ nanocomposite do not induce toxicity over MG-63 and did not aggravate LDH leakage in contrast to CF. The histopathological investigations on albino rats confirmed significantly improved regeneration of bone in the repair of a critical-size [8 mm] calvarium defect. Therefore, CFZ3 nanocomposite scaffold represents a simple, off-the-shelf solution to the combined challenges associated with bone defects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Background: Considering the disproportionate burden of delayed traumatic brain injury (TBI) management in low- and middle-income countries (LMICs), there is pressing demand for investigations. Therefore, our study aims to evaluate factors delaying the continuum of care for the management of TBIs in LMICs., Methods: A systematic review was conducted with PubMed, Scopus, Google Scholar and Cumulative Index to Nursing and Allied Health Literature (CINAHL). Observational studies with TBI patients in LMIC were included. The factors affecting management of TBI were extracted and analyzed descriptively., Results: A total of 55 articles were included consisting of 60,603 TBI cases from 18 LMICs. Road traffic accidents (58.7%) were the most common cause of injury. Among included studies, factors contributing to prehospital delays included a poor referral system and lack of an organized system of referral (14%), long travel distances (11%), inadequacy of emergency medical services (16.6%), and self-treatment practices (2.38%). For in-hospital delays, factors such as lack of trained physicians (10%), improper triage systems (20%), and absence of imaging protocols (10%), lack of in-house computed tomography scanners (35%), malfunctioning computed tomography scanners (10%), and a lack of invasive monitoring of intracranial pressure (5%), limited theater space (28%), lack of in-house neurosurgical facilities (28%), absence of in-house neurosurgeons (28%), and financial constraints (14%) were identified., Conclusions: Several factors, both before and during hospitalization contribute to delays in the management of TBIs in LMICs. Strategically addressing these factors can help overcome delays and improve TBI management in LMICs., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The present study was conducted to assess the growth performance, morphometric traits, muscle chemical composition and cholesterol content in four phenotypes of naked neck chicken (black, white-black, light brown and dark brown). A total of 320-day-old chicks, 80 from each phenotype, were randomly stratified into 20 replicates (16/replicate), according to a completely randomized design. The results showed higher final body weight, weight gain, and better FCR in both light brown and dark brown phenotypes whereas time of gains was found to be greater in dark brown phenotype. Keel length and shank circumference were greater in dark brown whereas wing spread was found to be higher in light brown phenotype. Drumstick circumference and body length did not show any significant differences (P > 0.05) across the phenotypes. Dry matter was found to be higher in white black, crude protein in black, white black and dark brown, moisture in light brown, and cholesterol content in black whereas ether extract and ash content were found to be greater in black and white black phenotypes. In conclusion, both light brown and dark brown phenotypes showed superior growth performance and morphometric traits. Similarly, from a health point of view, the dark brown and light brown phenotypes seem superior because their cholesterol content was low. Thus, it is strongly recommended that there should be a conscious effort to improve economically important traits of the light and dark brown birds to be used as dual-purpose slow growing chicken, especially in developing countries., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Competing Interests: Declaration of competing interest None.

Biomimetic nanocomposites containing hydroxyapatite and natural polymers are promising candidates for bone grafting. In this work, a tricomponent bioactive nanocomposite (nHA-CH-TFSP) assembling nano-hydroxyapatite (nHA), Chitosan (CH) and Trigonella foenum graecum seed polysaccharide (TFSP) was developed using co-precipitation method and investigated against bicomponent nHA-CH nanocomposite for bone tissue engineering. In contrast to nHA-CH nanocomposite, nHA-CH-TFSP nanocomposite exhibited rough and interconnected porous structure as revealed by SEM with the porosity (60.3 ± 0.17) lying in the range of cancellous bone. The incorporation of TFSP in nHA-CH substantially enhanced the in vitro water absorption capacity and protein adsorption ability along with appropriate biodegradation rate. Additionally, the nHA-CH-TFSP nanocomposite exhibited superior antibacterial activity. The nHA-CH-TFSP evinced a compressive strength of 6.7 ± 0.24 MPa and a compressive modulus of 100 ± 1.4 MPa, which fulfill the strength requisite of cancellous bone and could provide strong support for the growth of osteoblasts cells. Furthermore, the in vitro bioactivity study demonstrated its excellent biomineralization capacity in comparison to nHA-CH. The synthesized nHA-CH-TFSP nanocomposite exhibited better cytocompatibility towards the MG-63 cells along with its haemocompatible nature. Taken together the results of the present study indicate that nHA-CH-TFSP could serve as a prospective analogue for bone tissue engineering., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In this work, we have explored the polysaccharide nature of bael fruit gum (BFG) motivated from the current findings about the substantial role of the polysaccharides in bone tissue engineering. The nanocomposite scaffold (CSH-BFG) was prepared by blending BFG, nano-hydroxyapatite (n-HA) and chitosan (CS) by co-precipitation approach and compared with n-HA and CS binary system (CSH). The analysis of different properties was carried out by SEM, TEM, FTIR, XRD and mechanical testing. The CSH-BFG scaffolds revealed a rough morphology and uniform distribution of particles along with strong chemical interactions among different components compared to the CSH scaffold. The incorporation of BFG in the scaffold resulted in significant increase of the compressive strength, compressive modulus, protein adsorption, biodegradation and swelling behaviour. The ternary system exhibited superior antibacterial activity against different bacterial pathogens compared to the binary system. The in vitro biomineralization ability was elucidated from the formation of thick apatite layer complementing the result of ARS study in the CSH-BFG nanocomposite. Our findings also revealed that BFG reinforced CSH nanocomposite exhibited enhanced cell adhesion and proliferation, osteogenic differentiation along with phenomenal cytocompatibility. Overall, our results signified that the fabricated CSH-BFG nanocomposite carries enormous potential to be applied in the bone remodelling procedures., (Copyright © 2018. Published by Elsevier B.V.)

In this communication we describe the fabrication of nano-hydroxyapatite/chitosan-tamarind seed polysaccharide (n-HA/CS-TSP) nanocomposite with a weight ratio of 70/20/10, 70/15/15 and 70/10/20, respectively through a co-precipitation method. A comparative assessment of the properties of n-HA/CS-TSP and n-HA/CS nanocomposites was done by FT-IR, SEM-EDX, TEM, TGA/DTA, XRD and mechanical testing. The results suggested strong chemical interactions between the three components, decreased particle size and homogeneous dispersion of n-HA particles in n-HA/CS-TSP as compared to n-HA/CS. The n-HA/CS-TSP (70/10/20) showed the most porous and rough surface, enhanced thermal stability and highest compressive strength (4.0 MPa) and modulus (81 MPa). In addition, n-HA/CS-TSP (70/10/20) exhibited greater swelling character, acceptable degradation and increased biomineralization in simulated body fluid (SBF) as compared to n-HA/CS-TSP (70/20/10, 70/15/15) and n-HA/CS nanocomposites. The superior non-toxic response with MG-63 cells and better haemocompatibility was observed with n-HA/CS-TSP (70/15/15). Thereby, n-HA/CS-TSP nanocomposites could be promising alternative biomaterials in the field of bone tissue engineering compared to the n-HA/CS nanocomposite., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Purpose: To describe the use of multilevel models (MLMs) in evaluating the influence of contextual factors on HIV/AIDS, sexually transmitted infections (STIs), and risky sexual behavior (RSB) in sub-Saharan Africa., Methods: Ten databases were searched through May 29, 2016. Two reviewers completed screening and full-text review. Studies examining the influence of contextual factors on HIV/AIDS, STIs, and RSB and using MLMs for analysis were included. The Quality Assessment Tool for Quantitative Studies was used to evaluate study quality., Results: A total of 118 studies met inclusion criteria. Seventy-four studies focused on HIV/AIDS-related topics; 46 focused on RSB. No studies related to STIs other than HIV/AIDS met the eligibility criteria. Of five studies examining HIV serostatus and community socioeconomic factors, three found an association between poverty and measures of inequality and increased HIV prevalence. Among studies examining RSB, associations were found with numerous contextual factors, including poverty, education, and gender norms., Conclusions: Studies using MLMs indicate that several contextual factors, including community measures of socioeconomic status and educational attainment, are associated with a number of outcomes related to HIV/AIDS and RSB. Future studies using MLMs should focus on contextual-level interventions to strengthen the evidence base for causality., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Sn 1-x Co x O 2 (x=0.00, 0.01, 0.03, 0.05) nanoparticles (NPs) of average size ∼30-40nm were synthesized by co-precipitation method. The interaction of Co doped SnO 2 NPs with human serum albumin (HSA) and their photocatalytic and antimicrobial properties were studied. The structural analysis and morphology of Co doped SnO 2 NPs were analysed via X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FT-IR). Besides the structural and morphological analysis, the interaction of Co doped SnO 2 NPs with HSA were studied by UV-vis, Circular dichroism (CD) and fluorescence spectroscopy. Fluorescence quenching results suggest that Co doped SnO 2 NPs interact with an HSA molecule through static mechanism. CD indicates that α-helicity of HSA increases due to the interaction of Co doped SnO 2 NPs. The photocatalytic activities of the NPs with increased doping concentration were evaluated through a degradation process in the presence of methylene-blue (MB) dye under UV light irradiation, which exhibited that the surface area of NPs with increased doping concentration plays a major role in improving the photocatalytic activity. The antimicrobial effect of undoped and Co-doped SnO 2 NPs was determined using agar-well diffusion method and analyzed against gram-positive bacteria (Bacillus Cereus MC 2434). In our results, we have found that as the doping concentration increases into NPs, zone of inhibition increases, which could be ascribed to the production of ROS and large surface area of the NPs., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Herein, we report the synthesis of a novel tri-component nanocomposite system incorporating β-cyclodextrin (β-CD) with nano-hydroxyapatite (n-HA) and chitosan (CS), (n-HA/β-CD/CS) at three different temperatures via co-precipitation method. The chemical interactions and surface morphology have been evaluated by TEM, SEM and AFM techniques revealing the agglomerated nanoparticles in CS/n-HA-HA binary system whereas the ternary systems produced needle shaped nanoparticles dispersed homogeneously at low temperature with more porous and rougher surface. The addition of β-CD in CS/n-HA at low temperature decreased the particle size and raised the thermal stability as compared to CS/n-HA. The comparative hemolytic, protein adsorption and platelet adhesion studies confirmed the better hemocompatibility of n-HA/β-CD/CS-(RT,HT,LT) nanocomposites relative to CS/n-HA. The cell viability has been evaluated in vitro using MG-63 cell line which revealed superior non toxicity of n-HA/β-CD/CS-LT nanocomposite in comparison to n-HA/β-CD/CS-(RT,HT) and CS/n-HA nanocomposites. Thus it may be concluded that the orchestrated organic/inorganic n-HA/β-CD/CS-(RT,HT,LT) nanocomposites exhibited relatively higher cell viability of human osteoblast cells, stimulated greater osteogenesis, controlled biodegradation, enhanced antibacterial activity with excellent in-vitro biomineralization and remarkable mechanical parameters as compared to CS/n-HA nanocomposite and thus may provide opportunities for potential use as an alternative biomaterial for Bone tissue engineering applications., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Although malignant pleural mesothelioma (MPM) is generally a disease associated with more advanced age, the association of age, treatment, and outcomes has not been well-characterized. We evaluated the impact of age on outcomes in patients with MPM to provide data for use in the treatment selection process for elderly patients with potentially resectable disease., Patients and Methods: Overall survival (OS) of patients younger than 70 and 70 years or older with Stage I to III MPM who underwent cancer-directed surgery or nonoperative management in the Surveillance, Epidemiology, and End Results database (2004-2010) was evaluated using multivariable Cox proportional hazard models and propensity score-matched analysis., Results: Cancer-directed surgery was used in 284 of 879 (32%) patients who met inclusion criteria, and was associated with improved OS in multivariable analysis (hazard ratio, 0.71; P = .001). Cancer-directed surgery was used much less commonly in patients 70 years and older compared with patients younger than 70 years (22% [109/497] vs. 46% [175/382]; P < .001), but patients 70 years and older had improved 1-year (59.4% vs. 37.9%) and 3-year (15.4% vs. 8.0%) OS compared with nonoperative management. The benefit of surgery in patients 70 years and older was observed even after propensity score-matched analysis was used to control for selection bias., Conclusion: Surgical treatment is associated with improved survival compared with nonoperative management for both patients younger than 70 years and patients aged 70 years or older., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Malaria remains common in sub-Saharan Africa, but it is frequently over-diagnosed and over-treated in hospitalized children. HIV is prevalent in many malaria endemic areas and may delay parasite clearance and increase mortality among children with malaria. This prospective cohort study enrolled children with suspected malaria between 3 months and 12 years of age hospitalized at two referral hospitals in Tanzania. Both a thick blood smear (BS) and a malaria rapid diagnostic test (mRDT) were performed. If discordant results were obtained, PCR was performed for Plasmodium falciparum. Malaria was confirmed if two out of three tests were positive. Malaria parasite densities were determined for two consecutive days after diagnosis and treatment of malaria. All participants were tested for HIV. Among 1492 hospitalized children, 400 (26.8%) were enrolled with suspected malaria infection. There were 196/400 (49.0%) males, and the median age was 18 [9-36] months. BS was positive in 95/400 (23.8%), and mRDT was positive in 70/400 (17.5%), with moderate agreement (Kappa=0.598). Concordant results excluded malaria in 291/400 (72.8%) and confirmed malaria in 56/400 (14.0%). PCR performed on 53 discordant results confirmed malaria in 1/39 of the BS-positive/mRDT-negative cases, and 6/14 of the BS-negative/mRDT-positive cases. The prevalence of confirmed malaria was 63/400 (15.8%). In multivariable logistic regression, malaria was associated with HIV (OR 3.45 [1.65-7.20], p=0.001). Current breastfeeding (OR 0.25 [0.11-0.56], p=0.001) and higher hemoglobin (OR 0.70 [0.60-0.81], p<0.001 per 1g/dL) were associated with decreased odds of malaria. Malaria parasite clearance was delayed in HIV-infected participants (p<0.001). Malaria is over-diagnosed even at referral centers in high transmission areas. Hospitalized HIV-infected children are more likely to have malaria and exhibit delayed clearance of parasites. Hospitals should consider using mRDTs as a first step for malaria testing among hospitalized children in sub-Saharan Africa., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Previous studies have raised concerns that video-assisted thoracoscopic (VATS) lobectomy may compromise nodal evaluation. The advantages or limitations of robotic lobectomy have not been thoroughly evaluated., Methods: Perioperative outcomes and survival of patients who underwent open versus minimally-invasive surgery (MIS [VATS and robotic]) lobectomy and VATS versus robotic lobectomy for clinical T1-2, N0 non-small cell lung cancer from 2010 to 2012 in the National Cancer Data Base were evaluated using propensity score matching., Results: Of 30,040 lobectomies, 7,824 were VATS and 2,025 were robotic. After propensity score matching, when compared with the open approach (n = 9,390), MIS (n = 9,390) was found to have increased 30-day readmission rates (5% versus 4%, p < 0.01), shorter median hospital length of stay (5 versus 6 days, p < 0.01), and improved 2-year survival (87% versus 86%, p = 0.04). There were no significant differences in nodal upstaging and 30-day mortality between the two groups. After propensity score matching, when compared with the robotic group (n = 1,938), VATS (n = 1,938) was not significantly different from robotics with regard to nodal upstaging, 30-day mortality, and 2-year survival., Conclusions: In this population-based analysis, MIS (VATS and robotic) lobectomy was used in the minority of patients for stage I non-small cell lung cancer. MIS lobectomy was associated with shorter length of hospital stay and was not associated with increased perioperative mortality, compromised nodal evaluation, or reduced short-term survival when compared with the open approach. These results suggest the need for broader implementation of MIS techniques., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

A novel ternary nanocomposite system incorporating hydroxyapatite, chitosan and starch (n-HA/CS-ST) has been synthesized by co-precipitation method at room temperature, addressing the issues of biocompatibility, mechanical strength and cytotoxicity required for bone tissue engineering. The interactions, crystallite size, surface morphology and thermal stability against n-HA/CS nanocomposite have been obtained by comparing the results of FTIR, SEM, TEM, DLS, XRD and TGA/DTA. A comparative study of bioactivity and thermal stability of n-HA/CS and n-HA/CS-ST nanocomposites revealed that the incorporation of starch as templating agent enhanced these properties in n-HA/CS-ST nanocomposite. A lower swelling rate of n-HA/CS-ST relative to n-HA/CS indicates a higher mechanical strength supportive of bone tissue ingrowths. The MTT assay on murine fibroblast L929 and human osteoblasts-like MG-63 cells and in vitro bioactivity of n-HA/CS-ST matrix referred superior non-toxic nature of n-HA/CS-ST nanocomposite and greater possibility of osteointegration in vivo respectively. Furthermore n-HA/CS-ST exhibited improved antibacterial property against both Gram-positive and Gram-negative bacteria relative to n-HA/CS., (Copyright © 2015. Published by Elsevier B.V.)

Background: Robotic distal pancreatectomy (RDP) is performed increasingly, but knowledge of the number of cases required to attain procedural proficiency is lacking. The aim of this study was to identify the learning curve associated with RDP at a high-volume pancreatic centre., Methods: Metrics of perioperative safety and efficiency for all consecutive RDPs were evaluated. Outcomes were followed to 90 days. Cumulative sum (CUSUM) analysis was used to identify inflexion points corresponding to the learning curve., Results: Between 2008 and 2013, 100 patients underwent RDP. There was no 90-day mortality. In two patients (2.0%), surgery was converted to laparotomy. Thirty procedures were performed for pancreatic adenocarcinoma. Precipitous operative time reductions from an initial operative time of 331 min were observed after the first 20 and 40 cases to 266 min and 210 min, respectively (P < 0.0001). The likelihood of readmission was significantly lower after the first 40 cases (P = 0.04), and non-significant reductions were observed in incidences of major (Clavien-Dindo Grade II or higher) morbidity and Grade B and C leaks, and length of stay., Conclusions: In this experience, RDP outcomes were optimized after 40 cases. Familiarity with the platform and dedicated training are likely to contribute to significantly shorter learning curves in future adopters., (© 2015 International Hepato-Pancreato-Biliary Association.)

The covalent binding of yeast alcohol dehydrogenase (YADH) enzyme complex in a series of magnetic crystalline Ni-Co nanoferrites, synthesized via sol-gel auto combustion technique was investigated. The structural analysis, morphology and magnetic properties of Ni-Co nanoferrites were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), vibrating-sample magnetometer (VSM), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FTIR). The comparative analysis of the HRTEM micrographs of bare magnetic nanoferrite particles and particles immobilized with enzyme revealed an uniform distribution of the particles in both the cases without undergoing change in the size which was found to be in the range 20-30 nm. The binding of YADH to Ni-Co nanoferrites and the possible binding mechanism have been suggested by comparing the FTIR results. The binding properties of the immobilized YADH enzyme were also studied by kinetic parameters, optimum operational pH, temperature, thermal stability and reusability. The immobilized YADH exhibits enhanced thermal stability as compared to the free enzyme over a wide range of temperature and pH, and showed good durability after recovery by magnetic separation for repeated use., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The Schiff base ligand, bis(indoline-2-one)triethylenetetramine (L) obtained from condensation of triethylenetetramine and isatin was used to synthesize the complexes of type, [ML]Cl(2) [M=Co(II), Ni(II), Cu(II) and Zn(II)]. L was characterized on the basis of the results of elemental analysis, FT-IR, (1)H and (13)C NMR, mass spectroscopic studies. The stoichiometry, bonding and stereochemistries of complexes were ascertained on the basis of results of elemental analysis, magnetic susceptibility values, molar conductance and various spectroscopic studies. EPR, UV-vis and magnetic moments revealed an octahedral geometry for complexes. L and its Cu(II) and Zn(II) complexes were screened for their antibacterial activity. Analgesic activity of Cu(II) and Zn(II) complexes was also tested in rats by tail flick method. Both complexes were found to possess good antibacterial and moderate analgesic activity., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The template condensation reaction between benzil and 3,4-diaminotoulene resulted mononuclear 12-membered tetraimine macrocyclic complexes of the type, [MLCl(2)] [M=Co(II), Ni(II), Cu(II) and Zn(II)]. The synthesized complexes have been characterized on the basis of the results of elemental analysis, molar conductance, magnetic susceptibility measurements and spectroscopic studies viz. FT-IR, (1)H and (13)C NMR, FAB mass, UV-vis and EPR. An octahedral geometry has been envisaged for all these complexes, while a distorted octahedral geometry has been noticed for Cu(II) complex. Low conductivity data of all these complexes suggest their non-ionic nature. The interactive studies of these complexes with calf thymus DNA showed that the complexes are avid binders of calf thymus DNA. The in vitro antibacterial studies of these complexes screened against pathogenic bacteria proved them as growth inhibiting agents., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The mononuclear Schiff base complexes of the type, [ML(CH(3)OH)(2)] [M = Co(II), Ni(II), Cu(II) and Zn(II)] have been synthesized by template condensation of L-leucine and glyoxal. The complexes have been characterized on the basis of the results of the elemental analysis, molar conductance, magnetic susceptibility measurements and spectroscopic studies viz, FT-IR, Mass, (1)H NMR and (13)C NMR spectra. The UV-vis and magnetic moment data revealed an octahedral geometry around Co(II), Ni(II) ion with distortion around Cu(II) ion complex confirmed by EPR data. The conductivity data show a non-electrolytic nature of the complexes. Absorption and fluorescence spectroscopic studies support that all the complexes exhibit a significant binding to calf thymus DNA., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The Schiff base ligand, N,N'-bis-(2-thiophenecarboxaldimine)-3,3'-diaminobenzidine (L) obtained from condensation of 2-thiophenecarboxaldehyde and 3,3'-diaminobenzidine, was used to synthesize the complexes of type, [M2L2]Cl4 [M=Co(II), Ni(II), Cu(II), Cd(II) and Hg(II)]. The newly synthesized ligand (L) was characterized on the basis of the results of elemental analysis, FT-IR, 1H NMR, 13C NMR, mass spectroscopic studies and single crystal X-ray crystallography. The characteristic resonance signals in 1H NMR and 13C NMR spectra indicated the presence of azomethine group as a result of condensation reaction. The stoichiometry, bonding and stereochemistries of complexes were ascertained on the basis of results of elemental analysis, magnetic susceptibility measurements, molar conductance and spectroscopic studies viz., FT-IR, 1H and 13C NMR, UV-vis and EPR. EPR, UV-vis and magnetic moment data revealed an octahedral geometry for complexes with distortion in Cu(II) complex and conductivity data show 1:2 electrolytic nature of complexes. Absoption and fluorescence spectroscopic studies supported that Schiff base ligand L and its Co(II), Ni(II) and Cu(II) complexes exhibited significant binding to calf thymus DNA. The complexes exhibited higher affinity to calf thymus DNA than the free Schiff base ligand L., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Glycine glutaric acid, a new organic compound has been synthesized and good quality single crystals were grown by slow evaporation technique. The structure of the grown crystal was elucidated by using single crystal XRD. The presence of the functional groups was confirmed by using FT-IR spectroscopy. The optical transparency was studied by using UV-vis spectrophotometer and it was found that the crystal is having high optical transparency. The thermal stability of the crystal was studied by using thermo-gravimetric and differential thermal analyses and found that it is stable up to 150°C. The room temperature dielectric studies were also carried out over the wide frequency range: 10 mHz to 10 MHz., (Copyright © 2010 Elsevier B.V. All rights reserved.)

The Schiff base ligand, N,N'-bis-(2-furancarboxaldimine)-3,3'-diaminobenzidene (L) obtained by condensation of 2-furaldehyde and 3,3'-diaminobenzidene, was used to synthesize the mononuclear complexes of the type, [M(L)](NO3)2 [M=Co(II), Ni(II), Cu(II) and Zn(II)]. The newly synthesized ligand, (L) and its complexes have been characterized on the basis of the results of the elemental analysis, molar conductance, magnetic susceptibility measurements and spectroscopic studies viz, FT-IR, 1H and 13C NMR, mass, UV-vis and EPR. EPR, UV-vis and magnetic moment data revealed a square planar geometry for the complexes with distortion in Cu(II) complex and conductivity data show a 1:2 electrolytic nature of the complexes. Absorption and fluorescence spectroscopic studies support that Schiff base ligand, L and its Cu(II) and Zn(II) complex exhibit significant binding to calf thymus DNA. The highest binding affinity in case of L may be due to the more open structure as compared to the metal coordinated complexes., (Copyright © 2010 Elsevier B.V. All rights reserved.)

14 and 16 membered Schiff base macrocyclic ligands, 7,14-dimethyl-5,12-di(N-amino)-2-methylphenyl-1,4,8,11-tetraaza-cyclotetradecane-4,7,11,14-tetraene (L(1)) and 8,16-dimethyl-6,14-di(N-amino)-2-methylphenyl-1,5,9,13-tetraaza-cyclohexadecane-5,8,13,16-tetraene (L(2)) were synthesized by condensation reaction between 2'-methyleacetoacetanilide and aliphatic diamines. The metal complexes of the types, [ML(1)](NO(3))(2) and [ML(2)(NO(3))(2)] [M = Co(II), Ni(II), Cu(II) and Zn(II)] were prepared by interaction of ligands, L(1) or L(2) with hydrated metal(II) nitrates. The ligands and their complexes were characterized by elemental analysis, IR, (1)H and (13)C NMR, EPR, UV-Vis spectroscopy, magnetic susceptibility, conductivity measurements and ESI-mass spectral studies. The results of elemental analyses, ESI-mass and conductivity measurements confirmed the stoichiometry of ligands and their complexes while the characteristic absorption bands and resonance peaks in IR and NMR spectra confirmed the formation of ligand frameworks around the metal ions. The square planar geometry for complexes derived from ligand L(1) and octahedral environment for complexes derived from ligand L(2) with distortion in Cu(II) complex have been confirmed on the basis of results of electronic and electron spin resonance spectral studies and magnetic moment measurements. Absorption and fluorescence spectral studies revealed different binding mode for complex, [CuL(1)](NO(3))(2) as compared with [CuL(2)(NO(3))(2)] on interaction with calf thymus DNA.

The template condensation reaction between glyoxal and 1,8-diaminonaphthalene resulted a few novel mononuclear 14-membered tetraimine macrocyclic complexes of the type, [MLX(2)] [M=Co(II), Ni(II), Cu(II) and Zn(II), for X=Cl or NO(3)]. The stoichiometry and the nature of the complexes have been deduced from the results of elemental analyses and conductance data. The formation of macrocyclic framework has been inferred from the appearance of imine upsilon(CN) and upsilon(MN) band in IR spectra and the resonance signals observed in (1)H and (13)C-NMR spectra. However, the overall geometry of the complexes has been assigned on the positions of bands in electronic spectra and magnetic moment data. The distortion in Cu(II) complexes has been deduced on EPR data. The thermal behavior of these complexes has been studied by TGA analysis. Absorption and circular dichroism studies on the complex proved a significant binding to calf thymus DNA.

The Schiff base ligand, N,N'-bis-(2-pyridinecarboxaldimine)-1,8-diaminonaphthalene (L), obtained by the condensation of 2-pyridinecarboxaldehyde and 1,8-diaminonaphthalene, has been used to synthesize the mononuclear complexes of the type [MLCl(2)] [M=Co(II), Ni(II), Cu(II) and Zn(II)]. The newly synthesized ligand (L) and its complexes have been characterized on the basis of results of elemental analysis, molar conductance, magnetic susceptibility measurements, Job's method and spectroscopic studies viz., FT-IR, Mass, (1)H and (13)C NMR. The UV-vis and magnetic moment data revealed an octahedral geometry around Co(II), Ni(II) and Cu(II) ions and conductivity data show a non-electrolytic nature of the complexes. Absorption and fluorescence spectroscopic studies support that Cu(II) complex exhibits significant binding to calf thymus DNA.

Schiff base tetraazamacrocyclic ligand, L (C(40)H(28)N(4)) and its complexes of types, [MLX(2)] and [CuL]X(2) (M=Co(II), Ni(II), Zn(II); X=Cl(-), NO(3)(-)) were synthesized and characterized by elemental analyses, mass, (1)H NMR, IR, UV-vis, magnetic susceptibility and molar conductance data. An octahedral geometry has been proposed for all the complexes except the copper(II) complexes which have a square planar environment. The reducing power of the Co(II) and Cu(II) complexes have been checked and compared. The ligand (L) and its complexes have also been screened against different fungi and bacteria in vitro.