Ultrahighly Sensitive Surface-Enhanced Raman Spectroscopy Film of Silver Nanoparticles Dispersed in Three Dimensions on a Thin Alumina Nanowire Framework.

To develop highly sensitive surface-enhanced Raman spectroscopy (SERS) films, various types of aggregated Ag nanowire (NW) and nanoparticle (NP) complex structures were fabricated using anodic aluminum oxide (AAO) templates and thermal evaporation. Aggregated AgNW structures with numerous tapered nanogaps were fabricated via Ag deposition on aggregated thin alumina nanowires of different lengths. AgNP complex structures were obtained by collapsing vertically aligned thin alumina nanowires 1 µm in length and depositing AgNPs on their tops and sides using surface tension during ethanol drying after functionalization. The Raman signal enhancement factors (EFs) of the samples were evaluated by comparing the SERS signal of the thiophenol (TP) self-assembled monolayer (SAM) on the nanostructures with the Raman signal of neat TP. EFs as high as ~2.3 × 107 were obtained for the optimized aggregated AgNW structure (NW length of 1 µm) and ~3.5 × 107 for the optimized AgNP complex structure. The large EF of the AgNP complex film is attributed mainly to the AgNPs dispersed in three dimensions on the sides of the thin alumina nanowires, strongly implying some important, relevant physics yet to be discovered and also a very promising nanostructure scheme for developing ultrahighly sensitive SERS films with EF > 108.

Safety of free fibula flap harvest in IIIA and IIIB tibio-peroneal trunk variations.

INTRODUCTION: In head and neck cancer malignancies, free fibula flap is the gold standard for reconstruction of segmental bone defects owing to its predictable anatomy, long bone length, and feasibility for multiple osteotomies. However, sometimes because of variations in anatomy of tibio-peroneal trunk, it is a dilemma for the surgeons to use free fibula flap for reconstruction. This case series aimed to evaluate the safety of harvest of fibula in such cases in terms of acute and chronic donor-site complications. MATERIAL AND METHODS: A retrospective study was conducted from January 2018 to May 2021. All the patients with tibio-peroneal trunk anomaly, diagnosed during surgery, who underwent successful harvest of the free fibula were included in the study and analyzed for the early major and minor donor wound complications, long-term donor complications, and late functional deficit using the Foot and Ankle Disability Index (FADI). RESULTS: Out of 714 free fibulae operated, 26 patients (3.6%) had such tibio-peroneal trunk variations: 22 (2.9%) cases of type III A and B anomalies and 4 (0.56%) cases of type III C anomalies. The average FADI score was 95.3%. No one had any difficulty in personal care and activity of daily living. CONCLUSIONS: The free fibula flap can be safely harvested in patients with type III A and B anomalies if vascularity of foot after clamping of peroneal vessels is good and anterior tibial vessels are normal.

First report of Fusarium incarnatum-equiseti species complex as the causal agent of pod rot of black gram (Vigna mungo L.) in India.

Black gram (Vigna mungo L.) is important pulse crop and is the third-most cultivated pulse in India (Swaminathan et al. 2023). In August 2022, pod rot symptoms were observed on a black gram crop with 80 to 92% disease incidence in the Crop Research Center, Govind Ballabh Pant University of Agriculture & Technology, Pantnagar (29.0222° N, 79.4908° E), Uttarakhand, India. Disease symptoms included white to salmon pink fungal-like growth over the pods. The symptoms were more severe initially at the tip of the pods, which expanded at later stages to cover the entire pod. Seeds present in the symptomatic pods were severely shrivelled and non-viable. Ten plants from the field were sampled to identify the causal agent. Symptomatic pods were cut into pieces, surface-disinfested with 70% ethanol for 1 min to reduce contaminants, rinsed with sterilized water three times, dried on sterilized filter paper, and aseptically placed on potato dextrose agar (PDA) amended with 30 mg/liter streptomycin sulphate. After 7 days of incubation at 25°C, three Fusarium-like (FUSEQ1, FUSEQ2, and FUSEQ3) isolates were purified by single spore transfer and subcultured on PDA. Fungal colonies on PDA were initially white to light pink, aerial, and floccose, and later on, colonies turned ochre yellowish to buff brown. After transfer to carnation leaf agar (Choi et al. 2014), isolates formed hyaline, 3 to 5 septate macroconidia, 20.4 to 55.6 × 3.0 to 5.0 µm (n = 50) with tapered, elongated apical cells and prominent foot-shaped basal cells. Chlamydospores were thick, intercalary, globose, and abundant in chains. No microconidia were observed. Based on morphological characters, the isolates were identified as belonging to the Fusarium incarnatum-equiseti species complex (FIESC) (Leslie and Summerell 2006). For molecular identification of the three isolates, total genomic DNA was extracted using the PureLink® Plant Total DNA Purification Kit (Invitrogen™, ThermoFisher Scientific, Waltham, Massachusetts, United States) and used for amplification and sequencing of a portion of the internal transcribed spacer (ITS) region, the translation elongation factor-1 alpha (EF-1α) gene, and the second largest subunit of RNA polymerase (RPB2) gene (White et al. 1990; O'Donnell 2000). The sequences were deposited in the GenBank database (ITS: OP784766, OP784777, and OP785092; EF-1α: OP802797, OP802798, and OP802799; RPB2: OP799667, OP799668, and OP799669). Polyphasic identification carried out in fusarium.org indicated 98.72 % and 100% similarity of FUSEQ1 and FUSEQ2 respectively to F. clavum and FUSEQ3 had 98.72 % similarity to F. ipomoeae. Both of the identified species are members of the FIESC (Xia et al. 2019). Pathogenicity tests were carried out on 45-day-old potted plants of V. mungo with seed pods, which were kept in a greenhouse. Plants were sprayed with 10 ml of a conidial suspension of each isolate (107 conidia/ml). Control plants were sprayed with sterile distilled water. The plants were covered with sterilized plastic bags after inoculation to maintain humidity and kept in a greenhouse at 25 ± 2°C. Within ten days, all the inoculated plants showed symptoms similar to those observed in the field, whereas control plants were symptomless. The pathogenicity test was repeated twice. Fungi consistently reisolated from the symptomatic pods were confirmed by morphological characterization and molecular assays as described above to belong to the FIESC, whereas no fungus was isolated from control pods. Fusarium spp. causing pod rot in green gram (V. radiata L.) has also been reported from India (Buttar et al. 2022). To our knowledge, this is the first report of FIESC as a causal agent of pod rot of V. mungo in India. The pathogen has the potential to cause considerable economic and production losses in black gram, and for that reason, disease management strategies should be implemented.

Visible-Light-Induced Photocatalytic Trifluoromethylation of Bunte Salts: Easy Access to Trifluoromethylthiolated Synthons.

A metal-free visible-light-induced trifluoromethylation of Bunte salts of α-bromoketones/alkyl bromide/benzyl bromides/functionalized allyl (Baylis-Hillman) bromides has been accomplished using Langlois' reagent in the presence of inexpensive eosin Y as a photocatalyst to form the privileged trifluoromethylthiolated synthons. The method is straightforward, operationally simple, and endowed with broad substrate scope and good functional group tolerance.

Iodine-catalyzed thioallylation of indoles using Bunte salts prepared from Baylis-Hillman bromides.

Metal-free iodine-catalyzed regioselective thioallylation of indoles has been accomplished at room temperature using Bunte salts prepared from Baylis-Hillman bromides. The resulting multi-functional C3 thioallylated indoles exhibit ample structural diversity and good functional group tolerance.

Controlling the Multiscale Topography of Anodized Aluminum Oxide Nanowire Structures for Surface-Enhanced Raman Scattering and Perfect Absorbers.

In this study, a plasmonically active substrate is developed with the aim of controlling the perfect absorption and manipulating its optical properties for application in SERS (in NIR regime) and colorimetry. Based on modified fabrication method of anodized aluminum oxide (AAO), the cost-effective self-aggregation technique is presented to fabricate unique topography of bone-fire-like funnel-shaped collapsed and vertically aligned nanowire structures. The length of the nanowire and the modification of surface topography induced by capillary force inside the nanowire are set to structural parameters, and the effect of their changes is closely studied. After deposition of 40 nm gold (Au) film on numerous AAO nanowire structures with different wire lengths and unique topography, the localized surface plasmon resonance excitation is generated, and also its application on reflection and SERS spectra have been shown quantitatively. The length of the wire and surface topography modification are identified as suitable parameters to tune the reflection/absorption (from <40 to >90%) as well as colorimetric effect. Finally, an optimized wire length of Au-coated AAO substrate in SERS sensing application with 3.92 × 105 order of enhancement of rhodamine 6G (R6G) Raman signal is demonstrated.

Probing the Griffiths like phase, unconventional dual glassy states, giant exchange bias effects and its correlation with its electronic structure in Pr2-x Sr x CoMnO6.

Crystal, electronic structure, dc and ac magnetization properties of the hole substituted (Sr2+) and partially B-site disordered double perovskite Pr2-x Sr x CoMnO6 system have been investigated. The XRD pattern analysis showed a systematic decrease in the lattice parameters owing to the enhanced oxidation states of the Co/Mn ions. The electronic structure study by XPS measurements suggested the presence of mixed valence states of the B-site ions (Co2+ /Co3+ and Mn3+ /Mn4+) with significant enhancement of the average oxidation states due to hole doping. The mere absence of electronic states near the Fermi level in the valence band (VB) spectra for both pure (x = 0.0) and Sr doped (x = 0.5) systems indicated the insulating nature of the samples. Sr substitution is observed to increase the spectral weight near the Fermi level suggesting for an enhanced conductivity of the hole doped system. The dc magnetization data divulged a Griffiths like phase above the long-range ordering temperature. A typical re-entrant spin glass like phase driven by the inherent anti-site disorder (ASD) has been recognized by ac susceptibility study for both the pure and doped systems. Most interestingly, the emergence of a new cluster glass like phase (immediately below the magnetic ordering temperature and above the spin-glass transition temperature) solely driven by the Sr substitution has been unravelled by ac magnetization dynamics study. Observation of these dual glassy states in a single system is scarce and hence placed the present system amongst the rare materials. The isothermal magnetization measurements further probed the exhibition of the giant exchange bias effect originated from the interfacial exchange interactions due to existence of low temperature antiferromagnetic clusters embedded in the glassy matrix.

Investigation of multi-mode spin-phonon coupling and local B-site disorder in Pr2CoFeO6 by Raman spectroscopy and correlation with its electronic structure by XPS and XAS studies.

Electronic structure of Pr2CoFeO6 (at 300 K) was investigated by x-ray photoemission spectroscopy (XPS) and x-ray absorption spectroscopy techniques. All three cations, i.e. Pr, Co and Fe were found to be trivalent in nature. XPS valance band analysis suggested the system to be insulating in nature. The analysis suggested that Co3+ ions exist in low spin state in the system. Moreover, Raman spectroscopy study indicated the random distribution of the B-site ions (Co/Fe) triggered by same charge states. In temperature-dependent Raman study, the relative heights of the two observed phonon modes exhibited anomalous behaviour near magnetic transition temperature T N ~ 270 K, thus indicating towards interplay between spin and phonon degrees of freedom in the system. Furthermore, clear anomalous softening was observed below T N which confirmed the existence of strong spin-phonon coupling occurring for at least two phonon modes of the system. The line width analysis of the phonon modes essentially ruled out the role of magnetostriction effect in the observed phonon anomaly. The investigation of the lattice parameter variation across T N (obtained from the temperature-dependent neutron diffraction measurements) further confirmed the existence of the spin-phonon coupling.

Air-like plasmonics with ultralow-refractive-index silica aerogels.

The coupling of the surface plasmon near-field into the sensing medium is key to the sensitivity of surface plasmon-based sensing devices. A low-index dielectric is necessary for the sensing medium to support a highly-penetrating surface plasmon evanescent field that extends well into the dielectric medium. The air-like refractive index, n, of an aerogel substrate provides another dimension for ultralow-index plasmonic devices. In this paper, we experimentally observed an angular surface plasmon resonance dip at 74° with the ultralow-index aerogel substrate, as was expected from theory. We also demonstrated the comparatively high-sensitivity surface plasmon resonance wavelength, λ, while the change in Δλ/Δn with different substrates was studied in detail. A 740 nm-period metal grating was imprinted on aerogel (n = 1.08) and polydimethylsiloxane (PDMS; n = 1.4) substrates. The ultraviolet-visible-near-infrared spectra were observed in the reflection mode on the grating, resulting in sensitivities of 740.2 and 655.9 nm/RIU for the aerogel and PDMS substrates, respectively. Numerical simulations were performed to understand the near-field of the surface plasmon, which demonstrated resonances well correlated with the experimentally observed results. The near-field due to excitation of the surface plasmon polaritons is observed to be more confined and to penetrate deeper into the sensing medium when a low-index substrate is used.

Angle of His Accentuation Is a Viable Alternative to Dor Fundoplication as an Adjunct to Laparoscopic Heller Cardiomyotomy: Results of a Randomized Clinical Study.

BACKGROUND: There is no consensus regarding the type of anti-reflux procedure to be used as an adjunct to laparoscopic Heller cardiomyotomy (LHCM). The aim of this study was to compare Angle of His accentuation (AOH) with Dor Fundoplication (Dor) as an adjunct to LHCM. METHODS: A total of 110 patients with achalasia cardia presenting for LHCM from March 2010 to July 2015 were randomized to Dor and AOH. Symptom severity, achalasia-specific quality of life (ASQOL), new onset heartburn, and patient satisfaction were assessed using standardized scores preoperatively, at 3, 6 months, and then yearly. The primary outcome was relief of esophageal symptoms while secondary outcomes were new onset heartburn and ASQOL. RESULTS: Both groups were comparable with respect to the baseline demographic characteristics. There was no conversion to open and no mortality in either group. Median operative time was 128 min in AOH and 144 min in Dor group (p < 0.01). Mean follow-up was 36 months and was available in 98% patients. There was significant improvement in esophageal symptoms in both groups with no statistically significant difference between the two groups (p > 0.05). There was no difference in cumulative symptom scores between the two groups over the period of follow-up. New onset heartburn was seen in 11% in AOH and 9% in Dor group. Mean ASQOL score improved in both groups with no difference between the two groups (p = 0.83). Patient satisfaction was similar in both groups. CONCLUSION: AOH is similar to Dor as an adjunct to LHCM in safety and efficacy and can be performed in shorter time. CLINICAL REGISTRATION NUMBER: CTRI: REF/2014/06/007146.

Endoscopic Excision of Supracondylar Humeral Spur for Decompression of the Median Nerve and Brachial Artery.

The humeral supracondylar process and Struthers ligament comprise a relatively rare but well-known anatomic variant. They are usually asymptomatic but may produce clinical symptoms related to compression of the median nerve or brachial artery below the ligament. Previously, surgery has been performed with an open ligament release and supracondylar process excision. This article reports on the use of endoscopic findings and the method of ligament release and process excision. Endoscopy is a minimally invasive technique that provides excellent visualization and enables the surgeon to perform dissection with magnification and precision. It allows the surgeon to introduce open surgical techniques into the depths of the wound in a controlled manner. Because of the dead space created, there is a risk of hematoma formation. Many of the concepts used in open surgery are now being used for endoscopic surgery, and vice versa. The barriers and differences among endoscopic, arthroscopic, and open procedures are being broken down. We report another endoscopic technique, which is part of the ongoing evolution of musculoskeletal surgery.

Neurilemmoma of median nerve.

Neurilemmomas constitute one of the most common tumors of peripheral nerves. Rarer amongst them is their occurrence in median nerve in the region of arm. A sixteen-year-old female presented with painless mass in right arm which was non-tender on palpation with positive Tinel's sign and no motor or sensory deficit in the affected arm. Ultrasound examination revealed an eccentrically arising mass of size 19 × 11 mm along median nerve. MRI study revealed a mass homogenously isointense on T1 weighted images and hyperintense in T2 weighted images placed eccentrically in relation to median nerve in arm. Excisional biopsy under loupe magnification was carried out which revealed the mass to be neurilemmoma. This slowly growing benign tumor of peripheral nerves with an incidence of 5% with 14% involvement of Median nerve can be enucleated from the nerve with little or no damage. In spite of advanced imaging studies the mass cannot be differentiated preoperatively from another peripheral nerve sheath tumor neurofibroma. Both these tumors although bearing some clinical and imaging resemblance carry different intraoperative findings, histopathological features and post-operative results.

The role of tranexamic acid in reducing blood loss in total knee replacement.

BACKGROUND: Total knee arthroplasty is associated with significant perioperative blood loss which may necessitate blood transfusion. In this prospective randomised case control study we analysed the efficacy and safety of tranexamic acid in reducing perioperative blood loss and requirement of blood transfusion in total knee arthroplasty. METHODS: Fourteen patients (group A) undergoing total knee replacement were given intravenous tranexamic acid twice, once ten minutes before tourniquet deflation and once after four hours. Thirteen patients (group B) were observed as a separate group without the administration of the drug. Total perioperative blood loss, need of blood transfusion and D-dimer assay were analysed subsequently. RESULTS: The average blood loss in the first group was 266.2 ml and in the second group was 667.5 ml (p < 0.001). average requirement of transfusion in both the groups were 0.54 and 1.6 units of blood respectively (p < 0.001). There was no case of deep vein thrombosis or any other untoward effects. CONCLUSION: Hence from these evidences it was concluded that administration of tranexamic acid during total knee replacement helps to reduce blood loss without increasing the risk of deep vein thrombosis.