Dynamic indoor free-space optical communication enabled by beam steering and beam shaping.

Indoor free-space optical communication (FSO) provides orders of magnitude larger usable bandwidth compared to radio-frequency links but suffers from an intrinsic trade-off between areal coverage and received power. In this paper, we report a dynamic indoor FSO system enabled by a line-of-sight optical link featuring advanced beam control capabilities. The optical link herein utilizes a passive target acquisition scheme by combining a beam steering and beam shaping transmitter with a receiver adorned with a ring-shaped retroreflector. When controlled by an efficient beam scanning algorithm, the transmitter is capable of locating the receiver with millimeter-scale accuracy over a distance of 3 m with a full viewing angle of ±11.25∘ in the vertical direction and ±18.75∘ in the horizontal direction within 1.162±0.005s, regardless of the receiver's positions. We also demonstrate 1 Gbit/s data rate with bit error rates below 4×10-7 using an 850 nm laser diode with only 2 mW of output power.

A systematic review and meta-analysis of long COVID symptoms.

BACKGROUND: Ongoing symptoms or the development of new symptoms following a SARS-CoV-2 diagnosis has caused a complex clinical problem known as "long COVID" (LC). This has introduced further pressure on global healthcare systems as there appears to be a need for ongoing clinical management of these patients. LC personifies heterogeneous symptoms at varying frequencies. The most complex symptoms appear to be driven by the neurology and neuropsychiatry spheres. METHODS: A systematic protocol was developed, peer reviewed, and published in PROSPERO. The systematic review included publications from the 1st of December 2019-30th June 2021 published in English. Multiple electronic databases were used. The dataset has been analyzed using a random-effects model and a subgroup analysis based on geographical location. Prevalence and 95% confidence intervals (CIs) were established based on the data identified. RESULTS: Of the 302 studies, 49 met the inclusion criteria, although 36 studies were included in the meta-analysis. The 36 studies had a collective sample size of 11,598 LC patients. 18 of the 36 studies were designed as cohorts and the remainder were cross-sectional. Symptoms of mental health, gastrointestinal, cardiopulmonary, neurological, and pain were reported. CONCLUSIONS: The quality that differentiates this meta-analysis is that they are cohort and cross-sectional studies with follow-up. It is evident that there is limited knowledge available of LC and current clinical management strategies may be suboptimal as a result. Clinical practice improvements will require more comprehensive clinical research, enabling effective evidence-based approaches to better support patients.

Structural Morphology and Optical Properties of Strontium-Doped Cobalt Aluminate Nanoparticles Synthesized by the Combustion Method.

The study of structural morphology and the optical properties of nanoparticles produced by combustion methods are gaining significance due to their multifold applications. In this regard, in the present work, the strontium-doped cobalt aluminate nanoparticles were synthesized by utilizing Co1-xSrxAl2O4 (0 ≤ x ≤ 0.5) L-Alanine as a fuel in an ignition cycle. Subsequently, several characterization studies viz., X-ray diffraction (XRD), energy-dispersive X-ray (EDX) analysis, high-resolution scanning electron microscopy (HRSEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet (UV) spectroscopy and vibrating sample magnetometry (VSM) were accomplished to study the properties of the materials. The XRD analysis confirmed the cubic spinel structure, and the average crystallite size was found to be in the range of 14 to 20 nm using the Debye-Scherrer equation. High-resolution scanning electron microscopy was utilized to inspect the morphology of the Co1-xSrxAl2O4 (0 ≤ x ≤ 0.5) nanoparticles. Further, EDS studies were accomplished to determine the chemical composition. Kubelka-Munk's approach was used to determine the band gap, and the values were found to be in the range of 3.18-3.32 eV. The energy spectra for the nanoparticles were in the range of 560-1100 cm-1, which is due to the spinel structure of Sr-doped CoAl2O4 nanoparticles. The behavior plots of magnetic induction (M) against the magnetic (H) loops depict the ferromagnetic behavior of the nanomaterials synthesized.

A Passive Wideband Noise-Canceling Mixer-First Architecture With Shared Antenna Interface for Interferer-Tolerant Wake-Up Receivers and Low-Noise Primary Receivers.

Wake-up receivers (WuRX) present an opportunity to reduce average power consumption of IoT transceivers, however achieving sensitivity and interferer tolerance while providing wideband matching and sharing an antenna interface present a significant challenge for existing architectures. This paper presents a primary/WuRX which utilizes a quadrature hybrid coupler based N-Path mixer first architecture to simultaneously achieve low noise, wideband matching and a shared antenna interface. The passive-mixer first approach and a two-code modulated multi-tone signaling scheme provide interferer tolerance in the WuRX. The paper analyzes gain/power trade-offs in the proposed architecture in the context of noise impact with multi-tone WuRX signaling. The proposed architecture is implemented in 65 nm CMOS and occupies 2.25 mm 2. The primary RX achieves 3.8 dB NF and 0.75 dBm out-of-band P1dB with 440µW power consumption. The WuRX achieves -86 dBm sensitivity for 10kb/s data rate and up to -40 dB signal-to-interferer ratio (SIR) with 171µW power consumption.

Optimization of protease production from Bacillus halodurans under solid state fermentation using agrowastes.

Marine microbes are potential source for novel metabolites. They are efficient in producing these metabolites utilizing agrowastes. Protease is one of the enzymes which find wide industrial applications. In the present study, protease producing bacteria was isolated from marine sediments and the organism was identified as Bacillus halodurans. The organism was subjected to protease production under solid state fermentation (SSF) using different agrowastes as substrates. Among the substrates used, wheat bran yielded maximum quantity of protease. The fermentation process was carried out under different cultural conditions to optimize the parameters influencing the enzyme production. The results of the stain removal studies by the enzyme revealed the increased efficiency of the microbial enzyme than the commercial detergent.

Facilitating the gut brain axis by probiotic bacteria to modulate neuroimmune response on lead exposed zebra fish models

Unravelling the efficacy of gut biome has a major impact on health. An unbalanced microbiome composition is linked to many common illnesses such as gut dysbiosis, mental deformities and immunological imbalance. An optimistic influence on the gut biome can be made by consumingprobiotics. This would stimulate neuroprotection and immunomodulation intended by heavy metals pollution. Lead is a major source of neurotoxin that can induce neural deformities. Lactobacillusspecies isolated from curd were characterized to confirm its specificity. Zebra fish was reared at standard conditions and preclinical assessment on the intensity of induced neurotoxin lead was performed. The embryo toxic assay, immunomodulation effects and animal behavioural models endorsed the consequence of neurotoxicity. Different concentrations of bacterial isolate with standard antidepressant was considered for analysing the vigour of toxicity and its influence on cognitive behaviour by novel tank diving method. The restrain in the animal behaviour was also conferred by all the test samples with a decreased bottom dwelling time which was authenticated with haematology and histopathological studies. The alterations in morphology of the lymphocytes were balanced by the treated test samples. This study paves a twofold potential of probiotic as neuroprotectant and immune modulator against heavy metal toxicity.

A 6-Transistor Ultra-Low Power CMOS Voltage Reference with 0.02%/V Line Sensitivity.

This work presents a technique for design of ultra-low power (ULP) CMOS voltage references achieving extremely low line sensitivity while maintaining state-of-the-art temperature insensitivity through the use of a 6-transistor (6T) structure. The proposed technique demonstrates good performance in sub-100 nm CMOS technologies. The 65-nm CMOS implementation occupies only 840 µm2 of area and consumes 28.6 pA from a 0.5 V supply. Measurements from 6 samples from the same wafer show an average line sensitivity of 0.02 %/V, a 10X improvement over previous 65 nm implementations, and an average temperature coefficient of 99.2 ppm/°C.

Associations between childhood cancer treatment and tooth agenesis.

AIM: The aim of this study was to determine the prevalence of dental developmental disturbances in long-term survivors of childhood malignancies in New Zealand children. This study reports associations with potential risk factors to inform oncologists and dentists of the likelihood of dental abnormalities. METHODS: The study population was children aged 14-16 years old who were diagnosed with cancer prior to 10 years of age. A total of 156 children were eligible, of which 59 participated in this study. The indices used in this study were Holtta's Defect Index (HDI), and Oral Health Impact Profile-14 (OHIP-14). RESULTS: The prevalence of agenesis was 15.3%, microdontia 6.8% and root abnormalities 32.2%. Cyclophosphamide equivalent doses above 8,000mg/m2, stem cell therapy (SCT), and head and neck radiation therapy (HNRT) were associated with a higher mean number of teeth missing due to agenesis. SCT and HNRT were associated with a higher total HDI. A binary logistic regression was carried out to determine the odds of agenesis and found that HNRT was the main contributing factor (OR=7.7, p-value=0.04). The linear regression model found that dactinomycin and agenesis correlated with the largest mean OHIP-14. CONCLUSION: This study found that childhood cancer survivors in New Zealand had a high prevalence of developmental dental abnormalities and it identified potential risk factors related to their cancer treatment. Inequitable access to oral rehabilitation for this patient group argues for a mechanism for consistent improved access to publicly funded dental care across district health boards in New Zealand.

Isolated Infarction of the Splenium: A Rare Presentation of Mild Head Injury.

Posttraumatic cerebral infarction (PTCI) is a devastating complication of traumatic brain injury. It is usually seen in patients with moderate-to-severe head injury with a reported incidence of 1.9%-10.4%. Brain shift associated with the traumatic intracranial space-occupying lesions with or without severe cerebral edema is the most common mechanism underlying the PTCI. Without associated direct vascular injury, isolated PTCI is very rare after mild head injury. Such cases of PTCI following mild head injury have been reported in children in whom they usually affect the gangliocapsular region supplied by the lenticulostriate arteries. Such infarcts in adults are extremely rare. Although the exact pathogenesis is not clear, vasospasm or shearing-associated intimal tear is proposed to be the cause for this infarct. Other common causes of cerebral infarction should be ruled out before making such a diagnosis. Unlike PTCI associated with a severe head injury, cerebral infarction following mild head injury is expected to have a better neurological outcome.

Raman spectroscopic characterisation of resin-infiltrated hypomineralised enamel.

Raman spectroscopy was used to investigate how the effect of pre-treatment protocols, with combinations of hydrochloric acid (HCl), sodium hypochlorite (NaOCl) and hydrogen peroxide (H2O2), for molar-incisor hypo-mineralisation (MIH) altered the penetration depth of polymer infiltrants (ICON, DMG, Hamburg, Germany). Furthermore, the effect on the structure of the MIH portions of the teeth with treatment is examined using multivariate analysis of spectra. It was found that pre-treatment protocols improved penetration depths. The structure of the MIH portion post-treatment appeared much closer to that of normal enamel suggesting a diminution of protein in the MIH region with treatment.

Mass in the left atrial appendage: a therapeutic dilemma.

This is a case of a persistent mobile mass in the left atrial appendage in which 3-dimensional transesophageal echocardiography provided excellent definition of the contour of the mass and helped in comparison during follow-up. The mass was incidentally found before atrial fibrillation ablation and initially thought to be a thrombus. As it persisted almost unchanged despite adequate anticoagulation, a tumour such as a fibroelastoma became the leading possibility, presenting us with a management dilemma. Ablation was cancelled, and, because the mass was stable with no embolic sequelae, a conservative approach was adopted. The patient was discharged on long-term anticoagulation.

Antiplatelet and antithrombin strategies in acute coronary syndrome: state-of-the-art review.

Antiplatelet and antithrombotic agents significantly alter the clinical course of patients with acute coronary syndrome (ACS) and hence form the bedrock of the management pathway of this closely related continuum of coronary pathologies. The contemporary therapeutic armamentarium for the treatment of ACS now reflects the many technical and pharmacological advances that took place over the last two decades. In the original 1996 American College of Cardiology/ American Heart Association (ACC/AHA) guidelines for the management of acute myocardial infarction, only one antiplatelet agent (Aspirin) and one anticoagulant (unfractionated heparin) were recommended as class I therapies. Since then many newer agents have been developed and approved for routine clinical use in ACS patients. Recent research has focussed on improving efficacy on one hand and reducing bleeding complications on the other. This review focuses on the mechanism, efficacy, safety profile and clinical trial evidence of P2 Y12 receptor antagonist antiplatelet agents, glycoprotein IIb/IIIa receptor inhibitors (GPI), protease-activated receptor-1 (PAR-1) inhibitors, thrombin inhibitor bivalirudin and Factor Xa inhibitors fondaparinaux and rivaroxaban.