An Institutional Experience of Directional Deep Brain Stimulation and a Review of the Literature.

INTRODUCTION: Directional deep brain stimulation (dDBS) has been suggested to have a similar therapeutic effect when compared with the traditional omnidirectional DBS, but with an improved therapeutic window that yields optimized clinical effect owing to the ability to better direct, or "steer," electric current. We present our single-center, retrospective analysis of our experience in the use of dDBS in patients with movement disorders and provide a review of the literature. MATERIALS AND METHODS: We identified all patients with Parkinson disease (PD) and essential tremor (ET) who received a dDBS system between 2018 and 2022 and retrospectively examined characteristics of their longitudinal treatment. A total of 70 leads were identified across 42 patients (28 PD, 14 ET). RESULTS: Three types of systems were implemented (single-segment activation, 45.2% of patients; multiple independent current control, 50.0%; and local field potential sensing-enabled, 4.7%). The subthalamic nucleus or globus pallidus internus was targeted in PD, and the ventral intermediate nucleus of the thalamus in ET. Across the entire cohort (n = 70 leads), at initial programming, 54.2% of leads (n = 38) were programmed using directional stimulation. At the most recent reprogramming, 58.6% of leads (n = 41) implemented directionality. In patients with PD, the average decrease in levodopa-equivalent daily dose at six months after implantation was 35.4% ± 39.2%. Despite the ability to steer current to relieve stimulation-induced side effects, ten leads in six patients required surgical revision owing to electrode malposition. CONCLUSIONS: We show wide adaptability and implementation of directional stimulation, adding to the growing compendium of real-world uses of dDBS therapy. We used directionality to improve clinical response in both patients with PD and patients with ET and found that its programming flexibility was used at high rates long after implantation and initial programming. In patients with PD, dDBS led to a significant reduction in dopaminergic medication, suggesting sustained clinical improvement. Nonetheless, accurate surgical placement remains necessary to ensure optimal clinical outcomes.

Let's make size not matter: tumor control and toxicity outcomes of hypofractionated Gamma Knife radiosurgery for large brain metastases.

PURPOSE: Management of patients with large brain metastases poses a clinical challenge, with poor local control and high risk of adverse radiation events when treated with single-fraction stereotactic radiosurgery (SF-SRS). Hypofractionated SRS (HF-SRS) may be considered, but clinical data remains limited, particularly with Gamma Knife (GK) radiosurgery. We report our experience with GK to deliver mask-based HF-SRS to brain metastases greater than 10 cc in volume and present our control and toxicity outcomes. METHODS: Patients who received hypofractionated GK radiosurgery (HF-GKRS) for the treatment of brain metastases greater than 10 cc between January 2017 and June 2022 were retrospectively identified. Local failure (LF) and adverse radiation events of CTCAE grade 2 or higher (ARE) were identified. Clinical, treatment, and radiological information was collected to identify parameters associated with clinical outcomes. RESULTS: Ninety lesions (in 78 patients) greater than 10 cc were identified. The median gross tumor volume was 16.0 cc (range 10.1-56.0 cc). Prior surgical resection was performed on 49 lesions (54.4%). Six- and 12-month LF rates were 7.3% and 17.6%; comparable ARE rates were 1.9% and 6.5%. In multivariate analysis, tumor volume larger than 33.5 cc (p = 0.029) and radioresistant histology (p = 0.047) were associated with increased risk of LF (p = 0.018). Target volume was not associated with increased risk of ARE (p = 0.511). CONCLUSIONS: We present our institutional experience treating large brain metastases using mask-based HF-GKRS, representing one of the largest studies implementing this platform and technique. Our LF and ARE compare favorably with the literature, suggesting that target volumes less than 33.5 cc demonstrate excellent control rates with low ARE. Further investigation is needed to optimize treatment technique for larger tumors.

Synthesis of Aza-Bridged Perhydroazulene Chimeras of Tropanes and Hederacine A.

We report the synthesis of two novel azaperhydroazulene tropane-hederacine chimeras A and B, which contain an 8-azabicyclo[3.2.1]octane ring and a 7-azabicyclo[4.1.1]octane ring, respectively. The synthesis of both chimeras was achieved by epoxide ring opening and was governed by the stereochemistry of the hydroxy-epoxide unit. Finally, a density functional theory study was conducted to explain the regioselectivity of the cyclization and the importance of the stereochemistry of the hydroxyl group.

Advances in Technical Aspects of Deep Brain Stimulation Surgery.

BACKGROUND: Deep brain stimulation has become an established technology for the treatment of patients with a wide variety of conditions, including movement disorders, psychiatric disorders, epilepsy, and pain. Surgery for implantation of DBS devices has enhanced our understanding of human physiology, which in turn has led to advances in DBS technology. Our group has previously published on these advances, proposed future developments, and examined evolving indications for DBS. SUMMARY: The crucial roles of structural MR imaging pre-, intra-, and post-DBS procedure in target visualization and confirmation of targeting are described, with discussion of new MR sequences and higher field strength MRI enabling direct visualization of brain targets. The incorporation of functional and connectivity imaging in procedural workup and their contribution to anatomical modelling is reviewed. Various tools for targeting and implanting electrodes, including frame-based, frameless, and robot-assisted, are surveyed, and their pros and cons are described. Updates on brain atlases and various software used for planning target coordinates and trajectories are presented. The pros and cons of asleep versus awake surgery are discussed. The role and value of microelectrode recording and local field potentials are described, as well as the role of intraoperative stimulation. Technical aspects of novel electrode designs and implantable pulse generators are presented and compared.

Assessment of groundwater quality in Ranchi district, Jharkhand, India, using water evaluation indices and multivariate statistics.

Groundwater is the most abundant liquid freshwater on earth. Rapid urbanization in developing nations (like India) has led to increased groundwater withdrawal, adversely affecting the physicochemical characteristics. Ranchi district, Jharkhand, is a part of the smart city mission development plan of the government of India. Hence, to ensure safe and clean drinking water, it is necessary to assess groundwater quality and devise development plans. Seventeen physicochemical properties and metal(loid)s contents were analyzed to determine the groundwater quality. Various pollution indices such as water quality index (WQI), metal evaluation index (MI), heavy metal pollution index (HPI), and modified degree of contamination (mCd) are evaluated using arithmetic weighted value index and presented in a map using Arc GIS inverse distance weighting interpolation method. Chemometric analyses such as correlation, principal component, and cluster analysis were done to identify the source and determine the pollution state. A multiple linear regression model is employed to predict the impact of heavy metal and metalloid concentration on the WQI of the region. WQI shows that groundwater quality in Khelari (100.95) and Bundu (92.52) regions are highly degraded, whereas MI and HPI suggest that Ormanjhi (MI = 53.98) and Rahe (HPI = 109.20) are highly affected by metal contamination. The mCd suggests that Ormanjhi (97.15) has the highest degree of contamination. The contaminant sources were natural (geogenic processes) and anthropogenic (mining and industrial emissions). The high metal(loid)s concentration may soon result in groundwater quality degradation in the metal-affected regions.

Analysis of factors leading to early termination in glioblastoma-related clinical trials.

PURPOSE: Terminated clinical trials are an inefficient use of financial, patient, and administrative resources. We reviewed ClinicalTrials.gov for completed and terminated clinical trials for glioblastoma multiforme (GBM) and compared reported characteristics of completed and terminated trials to identify factors associated with early trial termination. METHODS: ClinicalTrials.gov was queried to identify all completed and terminated GBM-related clinical trials. Trial characteristics were examined and the reason for trial termination was determined. Univariate analysis by Pearson's chi-square and a multivariate logistic regression were performed to identify independent predictors of early trial termination. RESULTS: We identified 886 completed and terminated GBM-related trials between 2003 and 2020. Of these, 175 (19.8%) were terminated prior to completion. The most common reason for termination was participant accrual difficulties, accounting for 63 (36.0%) terminated trials. Trial termination was associated with trials that reported a primary purpose of diagnosis relative to treatment (OR = 2.952, p = 0.001). CONCLUSION: Early termination of clinical trials investigating interventions for the treatment of GBM is associated with diagnostic trials relative to therapeutic trials. Patient accrual difficulties are the most commonly identified reason for early trial termination. Predictors of trial termination should be considered when designing GBM-related clinical trials to minimize the odds of early trial termination.

Inducing neuroplasticity through intracranial θ-burst stimulation in the human sensorimotor cortex.

The progress of therapeutic neuromodulation greatly depends on improving stimulation parameters to most efficiently induce neuroplasticity effects. Intermittent θ-burst stimulation (iTBS), a form of electrical stimulation that mimics natural brain activity patterns, has proved to efficiently induce such effects in animal studies and rhythmic transcranial magnetic stimulation studies in humans. However, little is known about the potential neuroplasticity effects of iTBS applied through intracranial electrodes in humans. This study characterizes the physiological effects of intracranial iTBS in humans and compare them with α-frequency stimulation, another frequently used neuromodulatory pattern. We applied these two stimulation patterns to well-defined regions in the sensorimotor cortex, which elicited contralateral hand muscle contractions during clinical mapping, in patients with epilepsy implanted with intracranial electrodes. Treatment effects were evaluated using oscillatory coherence across areas connected to the treatment site, as defined with corticocortical-evoked potentials. Our results show that iTBS increases coherence in the ß-frequency band within the sensorimotor network indicating a potential neuroplasticity effect. The effect is specific to the sensorimotor system, the ß band, and the stimulation pattern and outlasted the stimulation period by ∼3 min. The effect occurred in four out of seven subjects depending on the buildup of the effect during iTBS treatment and other patterns of oscillatory activity related to ceiling effects within the ß band and to preexistent coherence within the α band. By characterizing the neurophysiological effects of iTBS within well-defined cortical networks, we hope to provide an electrophysiological framework that allows clinicians/researchers to optimize brain stimulation protocols which may have translational value.NEW & NOTEWORTHY θ-Burst stimulation (TBS) protocols in transcranial magnetic stimulation studies have shown improved treatment efficacy in a variety of neuropsychiatric disorders. The optimal protocol to induce neuroplasticity in invasive direct electrical stimulation approaches is not known. We report that intracranial TBS applied in human sensorimotor cortex increases local coherence of preexistent ß rhythms. The effect is specific to the stimulation frequency and the stimulated network and outlasts the stimulation period by ∼3 min.

Unleashing the promise of emerging nanomaterials as a sustainable platform to mitigate antimicrobial resistance.

The emergence and spread of antibiotic-resistant (AR) bacterial strains and biofilm-associated diseases have heightened concerns about exploring alternative bactericidal methods. The WHO estimates that at least 700 000 deaths yearly are attributable to antimicrobial resistance, and that number could increase to 10 million annual deaths by 2050 if appropriate measures are not taken. Therefore, the increasing threat of AR bacteria and biofilm-related infections has created an urgent demand for scientific research to identify novel antimicrobial therapies. Nanomaterials (NMs) have emerged as a promising alternative due to their unique physicochemical properties, and ongoing research holds great promise for developing effective NMs-based treatments for bacterial and viral infections. This review aims to provide an in-depth analysis of NMs based mechanisms combat bacterial infections, particularly those caused by acquired antibiotic resistance. Furthermore, this review examines NMs design features and attributes that can be optimized to enhance their efficacy as antimicrobial agents. In addition, plant-based NMs have emerged as promising alternatives to traditional antibiotics for treating multidrug-resistant bacterial infections due to their reduced toxicity compared to other NMs. The potential of plant mediated NMs for preventing AR is also discussed. Overall, this review emphasizes the importance of understanding the properties and mechanisms of NMs for the development of effective strategies against antibiotic-resistant bacteria.

Functional Outcomes and Their Influencing Factors for the Surgical Management of T-type Acetabulum Fractures: A Prospective Single-Centre Study of 73 Patients.

Introduction T-type fractures of the acetabulum are uncommon injuries, typically resulting in poorer long-term outcomes compared to other patterns of acetabular fractures. Our main purpose is to analyse the epidemiology, functional outcomes, and factors affecting the functional outcomes of patients with T-type acetabular fractures. Methods This prospective, single-centre study included 73 patients with T-type and T with posterior wall acetabular fractures. They underwent treatment with open reduction internal fixation using plating through the modified Stoppa, Kocher-Langenbeck (KL), or dual approach. The post-operative reduction was assessed according to Matta's criteria, and functional outcomes were evaluated using the modified Harris hip score. Results Between September 2017 and January 2023, 53 patients underwent surgery for T-type fractures (72.6%), and 20 patients were treated for T with posterior wall acetabular fractures (27.4%). The minimum follow-up period was one year, with a mean follow-up of 3.5 years. Anatomical reduction emerged as the major contributing factor towards good functional outcomes compared to satisfactory reduction according to Matta's criteria (P value: 0.006). Overall, 65 patients (89%) achieved excellent to good modified Harris hip scores, while eight patients (11%) obtained fair to poor scores. Patients with T-type fractures demonstrated better functional outcomes compared to T with posterior wall fractures (P value: 0.031). Conclusion Anatomical reduction, as assessed by Matta's reduction criteria, serves as a predictor of favourable functional outcomes. T with posterior wall fractures exhibit poor outcomes in comparison to T-type fractures. The surgical approach employed does not influence the reduction or the final functional outcome of the patient.

Why are clinical trials of deep brain stimulation terminated? An analysis of clinicaltrials.gov.

Background: Although deep brain stimulation (DBS) has established uses for patients with movement disorders and epilepsy, it is under consideration for a wide range of neurologic and neuropsychiatric conditions. Objective: To review successful and unsuccessful DBS clinical trials and identify factors associated with early trial termination. Methods: The ClinicalTrials.gov database was screened for all studies related to DBS. Information regarding condition of interest, study aim, trial design, trial success, and, if applicable, reason for failure was collected. Trials were compared and logistic regression was utilized to identify independent factors associated with trial termination. Results: Of 325 identified trials, 79.7% were successful and 20.3% unsuccessful. Patient recruitment, sponsor decision, and device issues were the most cited reasons for termination. 242 trials (74.5%) were interventional with 78.1% successful. There was a statistically significant difference between successful and unsuccessful trials in number of funding sources (p = 0.0375). NIH funding was associated with successful trials while utilization of other funding sources (academic institutions and community organizations) was associated with unsuccessful trials. 83 trials (25.5%) were observational with 84.0% successful; there were no statistically significant differences between successful and unsuccessful observational trials. Conclusion: One in five clinical trials for DBS were found to be unsuccessful, most commonly due to patient recruitment difficulties. The source of funding was the only factor associated with trial success. As DBS research continues to grow, understanding the current state of clinical trials will help design successful future studies, thereby minimizing futile expenditures of time, cost, and patient engagement.

Organizing a Regional In-Person Medical Student Symposium in Neuroscience and Neurosurgery Research: A How-To Guide.

BACKGROUND: Medical students are increasingly seeking out research opportunities to build their skills and network with future colleagues. Medical student-led conferences are an excellent endeavor to achieve this goal. METHODS: The American Association of Neurological Surgeons (AANS) student chapter at the Donald and Barbara Zucker School of Medicine at Hofstra/Northwell designed an in-person medical student research symposium alongside the Northwell Health Department of Neurosurgery. Post-conference feedback forms were sent out digitally to student attendees to evaluate event planning and execution and responses were given on a scale of 1-5 (5 being the highest score). RESULTS: In December 2023, the Northeast Medical Student Research Symposium (NMSRS) was held with over 80 participants and 52 medical student presenters. Keynote speakers delivered lectures geared towards students interested in neurosurgery and neuroscience research, followed by an interactive poster board session and resident/attending networking dinner. After the conference, students affirmed that they learned more about neuroscience research after the event (mean: 4.3), were more inclined to attend other neuroscience research events in the future (mean: 4.7), and would attend this event if held next year (mean: 4.8). The poster sessions (mean: 4.75) and keynote lectures (mean: 5) were the highest rated events, while the resident/attending networking dinner (mean: 3.6) was a potential area for improvement. CONCLUSION: Regional in-person conferences are an excellent way to foster interest in neurosurgery and neuroscience research, network with like-minded peers, and prepare students for presentations at national meetings.

Local Field Potentials in Deep Brain Stimulation: Investigation of the Most Cited Articles.

Objective: Deep brain stimulation (DBS) allows for direct electrical stimulation of neural circuitry and recording of local field potentials (LFPs). A bibliometric analysis can be implemented to identify studies that have shaped a research field and influenced future study; however, no such analysis investigating the implementation of LFPs in DBS has been performed. The objective of the present study was to identify the most highly cited articles pertaining to DBS LFPs to identify and evaluate the research that has contributed the most to this growing field. Methods: The Science Citation Index of the Web of Science was implemented to identify the top 84 most cited articles pertaining to DBS LFPs. Information regarding the publication, including author information and study aims, was extracted. Results: The most highly cited articles had had a mean of 109 citations and had been published between 2002 and 2019, with a mode in 2016. The articles had predominantly investigated the subthalamic nucleus (68% of clinical studies) in humans (83.8% of clinical studies). The studies of humans had recruited a mean of 12.5 subjects. Most of the identified articles (56.0%) had reported class III clinical evidence. Conclusions: The implementation of DBS LFPs is a novel field that is rapidly growing. However, a need exists for more studies with larger patient cohorts and more randomized controlled trials to further elucidate the benefits of this technology. These results will allow for the identification and recognition of the most influential studies pertaining to DBS LFPs, appreciation of the current and future research trends, and inform us regarding areas warranting further investigation.

Exploring the Intersection of Artificial Intelligence and Neurosurgery: Let us be Cautious With ChatGPT.

BACKGROUND AND OBJECTIVES: ChatGPT is a novel natural language processing artificial intelligence (AI) module where users enter any question or command and receive a single text response within seconds. As AI becomes more accessible, patients may begin to use it as a resource for medical information and advice. This is the first study to assess the neurosurgical information that is provided by ChatGPT. METHODS: ChatGPT was accessed in January 2023, and prompts were created requesting treatment information for 40 common neurosurgical conditions. Quantitative characteristics were collected, and four independent reviewers evaluated the responses using the DISCERN tool. Prompts were compared against the American Association of Neurological Surgeons (AANS) "For Patients" webpages. RESULTS: ChatGPT returned text organized in paragraph and bullet-point lists. ChatGPT responses were shorter (mean 270.1 ± 41.9 words; AANS webpage 1634.5 ± 891.3 words) but more difficult to read (mean Flesch-Kincaid score 32.4 ± 6.7; AANS webpage 37.1 ± 7.0). ChatGPT output was found to be of "fair" quality (mean DISCERN score 44.2 ± 4.1) and significantly inferior to the "good" overall quality of the AANS patient website (57.7 ± 4.4). ChatGPT was poor in providing references/resources and describing treatment risks. ChatGPT provided 177 references, of which 68.9% were inaccurate and 33.9% were completely falsified. CONCLUSION: ChatGPT is an adaptive resource for neurosurgical information but has shortcomings that limit the quality of its responses, including poor readability, lack of references, and failure to fully describe treatment options. Hence, patients and providers should remain wary of the provided content. As ChatGPT or other AI search algorithms continue to improve, they may become a reliable alternative for medical information.

Perioperative Anxiolysis and Analgesic Effect after Premedication with Melatonin and Pregabalin in Total Hip Arthroplasty under Spinal Anaesthesia: A Prospective Comparative Trial.

Background: Preoperative anxiety plays a critical role in post-operative pain response and other outcomes. Melatonin is a naturally secreted hormone which has anxiolytic, sedative, and analgesic properties. Pregabalin, analogue of gabapentin which has property of anxiolytic and analgesic effects. Materials and Methods: Total 96 patients undergoing total hip arthroplasty, divided into 3 groups of 32 each and were given placebo (group I), melatonin 6 mg (group II), and pregabalin 150 mg (group III). Anxiety level, postoperative pain score, sedation level and duration as well as characteristics of spinal anaesthesia were assessed with other vital parameters. Results: Group I showed an increment in the anxiety score from baseline whereas in group II and group III, there was a decline in pre-operative anxiety score from baseline at all the periods of observation and more significantly in group III. Visual analogue scale (VAS) score and total dose of rescue analgesia were highest in group I, but group II and group III were comparable to each other. However, the durations of spinal anaesthesia and motor blockade showed a statistically significant difference with maximum duration in group III followed by II and then I. The level of sedation among the three groups were comparable at all the periods of observation. Conclusions: Pregabalin was found better for perioperative anxiolysis, post-operative analgesia and for prolongation of duration of spinal anaesthesia when compared to melatonin.

Inverted-Y Ureteric Duplication With Paraureteric Diverticulum Presenting With Bladder Outlet Obstruction in an Infant- A Diagnostic Dilemma.

The ectopic ureter and paraureteric diverticulum are 2 known common urological anomalies of pediatric patients. Another rare entity is inverted-Y ureteric duplication. We report a case of a 3-month-old boy presented with bladder outlet obstruction, where surgical excision of large bladder diverticulum with left ureter and small kidney was done. Histopathology confirmed the presence of inverted-Y ureteric duplication with left dysplastic kidney. The report defines the first case of infantile bladder outlet obstruction having the co-existing congenital genitourinary anomaly of inverted Y-partial ureteric duplication with obstructive ectopic ureter and ipsilateral paraureteric diverticula.

Outcomes of children with idiopathic steroid resistant nephrotic syndrome: a single centre observational study.

INTRODUCTION: Idiopathic steroid resistant nephrotic syndrome (SRNS) has variable outcomes in children. The primary objective of the present study was to assess the cumulative remission rate and the secondary objectives were to assess factors affecting the remission status, kidney function survival, and adverse effects of medications. METHODS: One hundred fourteen patients with SRNS were included. Calcineurin inhibitor-based treatment protocol along with prednisolone and angiotensin-converting enzyme inhibitor were used, and patients were followed over 5 years. RESULTS: Median age was 4.5 years; 53.5% of cases were between 1 to 5 years of age. Sixty-two patients (54.4%) were at initial stage and 52 (45.6%) were at a late SRNS stage. Median eGFRcr was 83.5 mL/min/1.73m2 at presentation. Of the 110 patients, 63 (57.3%) achieved remission [complete remission 30 (27.3%), partial remission 33 (30%)], and 47 (42.7%) had no remission. Kidney function survival was 87.3% and 14 cases (12.7%) had progression to CKD (G3-8, G4-3, G5-1, and G5D-2). Median duration of follow up was 36 months (IQR 24, 60). Age of onset, cyclosporine/tacrolimus, eGFRcr, and histopathology (MCD/FSGS) did not affect remission. Similarly, remission status in addition to age of onset, drug protocol, and histopathology did not significantly affect kidney function during a period of 5 years. Hypertension, cushingoid facies, short stature, cataract, and obesity were observed in 37.7, 29.8, 25.5, 17.5, and 0.7% of cases, respectively. CONCLUSION: About half of the cases achieved remission. Age of onset of disease, cyclosporine/tacrolimus use, and histopathological lesion neither affected remission status nor short-term kidney function survival in SRNS.

#Neurosurgery: A Cross-Sectional Analysis of Neurosurgical Content on TikTok.

Objectives: TikTok is a social media platform that has gained popularity and become a powerful engine to disseminate public health and medical information. To date, no study has characterized the qualities of popular TikTok videos related to neurosurgery, or assessed biases in the content of these videos. Methods: The TikTok web browser application was queried using "#neurosurgery" to identify neurosurgery-related videos. The top 100 videos meeting inclusion criteria were analyzed and video characteristics determined. Bias was assessed by the DISCERN scoring system using 3 independent reviewers. A Kruskal-Wallis H test was used to correlate video popularity with video characteristics and to correlate bias with creator and video type. Results: The 100 videos evaluated totaled 8.8 million likes, 104,718 comments, and 100,856 shares. The oldest video was posted February 2020 and the most recent March 2022. Videos were most commonly entertaining (n = 64, 64%), and educational (n = 46, 46%). Video popularity was associated with videos that aimed to entertain, and least associated with videos depicting neurosurgery lifestyle. Low DISCERN scores, indicating more biased content, were seen across the neurosurgical content with the entertaining video category demonstrating the highest bias. Conclusions: Neurosurgical content on TikTok contains a high degree of bias across all creator and video types. Entertaining videos are associated with the highest numbers of likes but also the greatest bias. These data may be used to guide institutions and neurosurgeons to grow interest in the field of neurosurgery and disseminate unbiased information while expanding their social media presence.

Characterization, Antioxidant, and Antimicrobial Properties of Mulberry Lattices.

In order to find the most advantageous bioactive compounds from mulberry latex for drug development in the near future, this study was conducted to characterize and evaluate antioxidant and antimicrobial properties from four different mulberry lattices (BR-2, S-1, AR-14, and S-146). The characterization of the lattices was performed by scanning electron microscopy with energy-dispersive X-ray spectroscopy, gas chromatography coupled to mass spectroscopy, and Fourier transform infrared spectroscopy. Further, screenings of the antioxidant and antimicrobial potential of selected lattices were performed in vitro using 2,2-diphenyl-1-picrylhydrazyl assay and agar well diffusion methods, respectively. Interestingly, the outcome of the current study revealed that tested mulberry lattices contain a considerable amount of bioactive phytoconstituents, particularly antimicrobial and antioxidant compounds, as revealed by chromatographic analysis. BR-2 latex was found to have significant antioxidant activity (75%) followed by S-146 (64.6%) and AR-14 (52.9%). The maximum antimicrobial activity was found in BR-2 latex compared to other tested latex varieties. The results of this investigation showed that mulberry latex from the BR-2 type may successfully control both bacterial and fungal infections, with the added benefit of having enhanced antioxidant capabilities.

Constraining extra dimensions using observations of black hole quasi-normal modes.

The presence of extra dimensions generically modify the spacetime geometry of a rotating black hole, by adding an additional hair, besides the mass M and the angular momentum J, known as the 'tidal charge' parameter, ß . In a braneworld scenario with one extra spatial dimension, the extra dimension is expected to manifest itself through - (a) negative values of ß , and (b) modified gravitational perturbations. This in turn would affect the quasi-normal modes of rotating black holes. We numerically solve the perturbed gravitational field equations using the continued fractions method and determine the quasi-normal mode spectra for the braneworld black hole. We find that increasingly negative values of ß correspond to a diminishing imaginary part of the quasi-normal mode, or equivalently, an increasing damping time. Using the publicly available data of the properties of the remnant black hole in the gravitational wave signal GW150914, we check for consistency between the predicted values (for a given ß ) of the frequency and damping time of the least-damped ℓ = 2 , m = 2 quasi-normal mode and measurements of these quantities using other independent techniques. We find that it is highly unlikely for the tidal charge, ß â‰² - 0.05 , providing a conservative limit on the tidal charge parameter. Implications and future directions are discussed.