Wide-field-of-view optical detectors for deep ultraviolet light communication using all-inorganic CsPbBr3 perovskite nanocrystals.

Optical wireless communication (OWC) links suffer from strict requirements of pointing, acquisition, and tracking (PAT) between the transmitter and receiver. Extending the narrow field-of-view (FoV) of conventional light-focusing elements at the receiver side can relax the PAT requirements. Herein, we use all-inorganic CsPbBr3 nanocrystals (NCs) to extend various optical concentrators' FOV to 60°, regardless of the original FOV values of the concentrators. Given the robustness of UV light against communication channel misalignment, the used CsPbBr3 NCs provide another advantage of converting transmitted UVC light into a green color that matches the peak absorption of the widely available Si-based detectors. We evaluated the feasibility of the reported wide FoV optical detectors by including them in deep UV OWC systems, deploying non-return-to-zero on-off keying (NRZ-OOK) and orthogonal-frequency division multiplexing (OFDM) modulation schemes. The NRZ-OOK and OFDM schemes exhibit stable communication over the 60° FoV, providing data transmission rates of 100 Mb/s and 71.6 Mb/s, respectively, a unique capability to the reported design.

The Chlamydia effector CpoS modulates the inclusion microenvironment and restricts the interferon response by acting on Rab35.

The obligate intracellular bacterium Chlamydia trachomatis inserts a family of inclusion membrane (Inc) proteins into the membrane of its vacuole (the inclusion). The Inc CpoS is a critical suppressor of host cellular immune surveillance, but the underlying mechanism remained elusive. By complementing a cpoS mutant with various natural orthologs and variants of CpoS, we linked distinct molecular interactions of CpoS to distinct functions. Unexpectedly, we found CpoS to be essential for the formation of inclusion membrane microdomains that control the spatial organization of multiple Incs involved in signaling and modulation of the host cellular cytoskeleton. While the function of CpoS in microdomains was uncoupled from its role in the suppression of host cellular defenses, we found the ability of CpoS to interact with Rab GTPases to be required not only for the manipulation of membrane trafficking, such as to mediate transport of ceramide-derived lipids (sphingolipids) to the inclusion, but also for the inhibition of Stimulator of interferon genes (STING)-dependent type I interferon responses. Indeed, depletion of Rab35 phenocopied the exacerbated interferon responses observed during infection with CpoS-deficient mutants. Overall, our findings highlight the role of Inc-Inc interactions in shaping the inclusion microenvironment and the modulation of membrane trafficking as a pathogenic immune evasion strategy. IMPORTANCE Chlamydia trachomatis is a prevalent bacterial pathogen that causes blinding ocular scarring and urogenital infections that can lead to infertility and pregnancy complications. Because Chlamydia can only grow within its host cell, boosting the intrinsic defenses of human cells may represent a novel strategy to fight pathogen replication and survival. Hence, CpoS, a Chlamydia protein known to block host cellular defenses, or processes regulated by CpoS, could provide new opportunities for therapeutic intervention. By revealing CpoS as a multifunctional virulence factor and by linking its ability to block host cellular immune signaling to the modulation of membrane trafficking, the present work may provide a foundation for such rationale targeting and advances our understanding of how intracellular bacteria can shape and protect their growth niche.

CNN-Aided Optical Fiber Distributed Acoustic Sensing for Early Detection of Red Palm Weevil: A Field Experiment.

Red palm weevil (RPW) is a harmful pest that destroys many date, coconut, and oil palm plantations worldwide. It is not difficult to apply curative methods to trees infested with RPW; however, the early detection of RPW remains a major challenge, especially on large farms. In a controlled environment and an outdoor farm, we report on the integration of optical fiber distributed acoustic sensing (DAS) and machine learning (ML) for the early detection of true weevil larvae less than three weeks old. Specifically, temporal and spectral data recorded with the DAS system and processed by applying a 100-800 Hz filter are used to train convolutional neural network (CNN) models, which distinguish between "infested" and "healthy" signals with a classification accuracy of ∼97%. In addition, a strict ML-based classification approach is introduced to improve the false alarm performance metric of the system by ∼20%. In a controlled environment experiment, we find that the highest infestation alarm count of infested and healthy trees to be 1131 and 22, respectively, highlighting our system's ability to distinguish between the infested and healthy trees. On an outdoor farm, in contrast, the acoustic noise produced by wind is a major source of false alarm generation in our system. The best performance of our sensor is obtained when wind speeds are less than 9 mph. In a representative experiment, when wind speeds are less than 9 mph outdoor, the highest infestation alarm count of infested and healthy trees are recorded to be 1622 and 94, respectively.

Compact scintillating-fiber/450-nm-laser transceiver for full-duplex underwater wireless optical communication system under turbulence.

The growing need for ocean monitoring and exploration has boosted underwater wireless optical communication (UWOC) technology. To solve the challenges of pointing, acquisition, and tracking (PAT) in UWOC technology, herein, we propose a 450-nm-laser/scintillating-fiber-based full-duplex (FD)-UWOC system for omnidirectional signal detection in real scenarios. The FD-UWOC system has a -3 dB bandwidth of 67 MHz with a low self-interference level of -44.59 dB. It can achieve a 250-Mbit/s data rate with on-off keying modulation scheme. The system's robustness was validated by operating over 1.5-m underwater channel with air-bubble-, temperature-, salinity-, turbidity-, and mobility-induced turbulence with a low outage probability. Under air-bubble-induced turbulence, the highest outage probability was 28%. With temperature-, salinity-, and turbidity-induced turbulence, the system performed adequately, showing a highest outage probability of 0%, 3%, and 4%, respectively. In mobile cases, the highest outage probability of the FD-UWOC system was 14%, compared to an outage probability of 100% without utilizing the fluorescent optical antenna. To further validate its robustness, a deployment test was conducted in an outdoor diving pool. The system achieved a 250-Mbit/s data rate over a 7.5-m working distance in the stationary case and a 1-m working range in the mobile case with a 0% outage probability. The scintillating-fiber-based detector can be employed in UWOC systems and would help relieve PAT issues.

PPE51 mediates uptake of trehalose across the mycomembrane of Mycobacterium tuberculosis.

The disaccharide trehalose is essential for viability of Mycobacterium tuberculosis, which synthesizes trehalose de novo but can also utilize exogenous trehalose. The mycobacterial cell wall encompasses two permeability barriers, the cytoplasmic membrane and the outer mycolic acid-containing mycomembrane. The ABC transporter LpqY-SugA-SugB-SugC has previously been demonstrated to mediate the specific uptake of trehalose across the cytoplasmic membrane. However, it is still unclear how the transport of trehalose molecules across the mycomembrane is mediated. In this study, we harnessed the antimycobacterial activity of the analogue 6-azido trehalose to select for spontaneous resistant M. tuberculosis mutants in a merodiploid strain harbouring two LpqY-SugA-SugB-SugC copies. Mutations mediating resistance to 6-azido trehalose mapped to the proline-proline-glutamate (PPE) family member PPE51 (Rv3136), which has recently been shown to be an integral mycomembrane protein involved in uptake of low-molecular weight compounds. A site-specific ppe51 gene deletion mutant of M. tuberculosis was unable to grow on trehalose as the sole carbon source. Furthermore, bioorthogonal labelling of the M. tuberculosis Δppe51 mutant incubated with 6-azido trehalose corroborated the impaired internalization. Taken together, the results indicate that the transport of trehalose and trehalose analogues across the mycomembrane of M. tuberculosis is exclusively mediated by PPE51.

Dual-wavelength luminescent fibers receiver for wide field-of-view, Gb/s underwater optical wireless communication.

Extending the field-of-view (FoV) of underwater wireless optical communication (UWOC) receivers can significantly ease the need for active positioning and tracking mechanisms. Two bundle of scintillating fibers emitting at 430- and 488-nm were used to detect two independent signals from ultraviolet and visible laser sources. A zero-forcing approach to minimize inter-channel crosstalk was further implemented. A net aggregated UWOC data rate of 1 Gb/s was achieved using two wavelengths and a non-return-to-zero on-off keying scheme.

Toward self-powered and reliable visible light communication using amorphous silicon thin-film solar cells.

Enhancing robustness and energy efficiency is critical in visible light communication (VLC) to support large-scale data traffic and connectivity of smart devices in the era of fifth-generation networks. To this end, we demonstrate that amorphous silicon (a-Si) thin-film solar cells with a high light absorption coefficient are particularly useful for simultaneous robust signal detection and efficient energy harvesting under the condition of weak light in this study. Moreover, a first-generation prototype called AquaE-lite is developed that consists of an a-Si thin-film solar panel and receiver circuits, which can detect weak light as low as 1 µW/cm2. Using AquaE-lite and a white-light laser, orthogonal frequency-division multiplexing signals with data rates of 1 Mb/s and 908.2 kb/s are achieved over a 20-m long-distance air channel and 2.4-m turbid outdoor pool water, respectively, under the condition of strong background light. The reliable VLC system based on energy-efficient a-Si thin-film solar cells opens a new pathway for future satellite-air-ground-ocean optical wireless communication to realize connectivity among millions of Internet of Things devices.

Rapid detection of Mycobacterium tuberculosis in sputum with a solvatochromic trehalose probe.

Tuberculosis (TB) is the leading cause of death from an infectious bacterial disease. Poor diagnostic tools to detect active disease plague TB control programs and affect patient care. Accurate detection of live Mycobacterium tuberculosis (Mtb), the causative agent of TB, could improve TB diagnosis and patient treatment. We report that mycobacteria and other corynebacteria can be specifically detected with a fluorogenic trehalose analog. We designed a 4-N,N-dimethylamino-1,8-naphthalimide-conjugated trehalose (DMN-Tre) probe that undergoes >700-fold increase in fluorescence intensity when transitioned from aqueous to hydrophobic environments. This enhancement occurs upon metabolic conversion of DMN-Tre to trehalose monomycolate and incorporation into the mycomembrane of Actinobacteria. DMN-Tre labeling enabled the rapid, no-wash visualization of mycobacterial and corynebacterial species without nonspecific labeling of Gram-positive or Gram-negative bacteria. DMN-Tre labeling was detected within minutes and was inhibited by heat killing of mycobacteria. Furthermore, DMN-Tre labeling was reduced by treatment with TB drugs, unlike the clinically used auramine stain. Lastly, DMN-Tre labeled Mtb in TB-positive human sputum samples comparably to auramine staining, suggesting that this operationally simple method may be deployable for TB diagnosis.

Best evidence topic: Should ventral hernia repair be performed at the same time as bariatric surgery?

A best evidence topic has been constructed using a described protocol. The three-part question addressed was: In morbidly obese patients undergoing bariatric surgery, when a ventral hernia is picked up in clinic or intraoperatively is concurrent repair of the hernia better than delayed repair after weight loss with regards to complication rates? Using the reported search, 179 papers were found. 5 studies were deemed to be suitable to answer the question. All 5 studies assessed were non randomised studies either retrospective or prospective and the overall quality of these studies was poor. The outcomes assessed were incidence of complications associated with hernia repair (recurrence, infection) and deferral of repair (small bowel obstruction). The patient's symptoms and anatomy is important in determining the timing of repair. The evidence does not provide a consensus for the optimal timing of ventral hernia repair for patients undergoing bariatric surgery, with some of the selected studies contradicting each other. However, the studies do affirm the risk of small bowel obstruction if hernias are left alone. The reported rate of surgical site infection is low when mesh repair is performed at the same time as weight loss surgery. Until large volume, high quality randomized control trials can be performed, a case by case approach is best, where the patients' symptoms, anatomy, type of bariatric surgery and their personal preferences are considered, and an open discussion on the risks and benefits of each approach is undertaken.

Cow's Milk Protein Allergy Mimicking Acrodermatitis Enteropathica.

Cow's milk protein allergy is an adverse immune reaction to one or more of the constituent proteins of milk obtained from any animal, most commonly alpha s 1-casein cow's milk. In many cases, the allergy is genetic in origin. The infants may experience symptoms within minutes after feeding (rapid onset) or commonly after 7-10 days of consuming the cow's milk (slower onset). Many children with cow's milk protein allergy develop symptoms in at least two of the following organ systems: gastrointestinal, skin and respiratory tract. Acrodermatitis Enteropathica (primary or secondary zinc deficiency) can also produce lesions in the skin and also gastro intestinal symptoms which can mimic milk protein allergy and differentiating between these two may be difficult. We are reporting a case of cow's milk protein allergy in an infant, which was initially diagnosed as Acrodermatitis Enteropathica and treated with zinc. The lesions did not subside completely even after achieving adequate zinc levels, but on stopping the cow's milk all the symptoms and signs disappeared completely and there was no recurrence on long term follow up.

A role for motor and somatosensory evoked potentials during anterior cervical discectomy and fusion for patients without myelopathy: Analysis of 57 consecutive cases.

BACKGROUND: Although the usage of combined motor and sensory intraoperative monitoring has been shown to improve the surgical outcome of patients with cervical myelopathy, the role of transcranial electric motor evoked potentials (tceMEP) used in conjunction with somatosensory evoked potentials (SSEP) in patients presenting with radiculopathy but without myelopathy has been less clear. METHODS: We retrospectively reviewed all patients (n = 57) with radiculopathy but without myelopathy, undergoing anterior cervical decompression and fusion at a single institution over the past 3 years, who had intraoperative monitoring with both tceMEPs and SSEPs. RESULTS: Fifty-seven (100%) patients presented with radiculopathy, 53 (93.0%) with mechanical neck pain, 35 (61.4%) with motor dysfunction, and 29 (50.9%) with sensory deficits. Intraoperatively, 3 (5.3%) patients experienced decreases in SSEP signal amplitudes and 4 (6.9%) had tceMEP signal changes. There were three instances where a change in neuromonitoring signal required intraoperative alteration of the surgical procedure: these were deemed clinically significant events/true positives. SSEP monitoring showed two false positives and two false negatives, whereas tceMEP monitoring only had one false positive and no false negatives. Thus, tceMEP monitoring exhibited higher sensitivity (33.3% vs. 100%), specificity (95.6% vs. 98.1%), positive predictive value (33.3% vs. 75.0%), negative predictive value (97.7% vs. 100%), and efficiency (91.7% vs. 98.2%) compared to SSEP monitoring alone. CONCLUSIONS: Here, we present a retrospective series of 57 patients where tceMEP/SSEP monitoring likely prevented irreversible neurologic damage. Though further prospective studies are needed, there may be a role for combined tceMEP/SSEP monitoring for patients undergoing anterior cervical decompression without myelopathy.

Rare case of intracranial Salmonella enteritidis abscess following glioblastoma resection: Case report and review of the literature.

BACKGROUND: Worldwide, Salmonella enteritidis (SE) is becoming a common cause of gastrointestinal infections by contaminated food products, mainly eggs. Extra-intestinal manifestations such as brain abscess are more commonly associated with Salmonella typhimurium and are rare in adults. We report the clinical features, treatment outcomes and risk factors predisposing our patient to Salmonella enteritidis brain abscess and discuss relevant literature. CASE DESCRIPTION: A 57-year-old-man developed SE subdural empyema, abscess and possible ventriculitis following reoperation for progression of a right temporal glioblastoma. He initially presented with rapidly worsening headaches over a few days, with a wound discharge and associated meningeal signs. An emergent wound washout revealed pus in the epidural, subdural space and resection cavity. An external ventricular drain (EVD) was placed and cultures revealed gram negative rods. Timely intervention, EVD, and antibiotics resulted in complete resolution. Nine cases of Salmonella abscess associated with primary brain tumor have been reported in literature, most frequently caused by SE in association with glioblastoma multiforme (GBM). We describe our management and outcome in addition to discussing neurosurgical literature on the reported cases. CONCLUSIONS: Re-operative tumor surgery has a higher incidence of post-operative infections, with Gram positive cocci being the most common pathogens. Predisposing factors reported for intracranial salmonellosis include compromised immunity, diabetes, HIV, and recent travel. Chronic corticosteroid use, multiple regimens of chemotherapy, and regions of tumor necrosis likely potentiate this rare infection in GBM patients.

Dyschromatosis Unwersalis Hereditaria.

A 50-year-old man had dyschromatosis universalis hereditaria manifesting as asymptomatic macular pigmentation and depigmentation present all over the body almost since birth. There was no atrophy or telangiectasis. In addition, the patient had associated features of solar elastotic syndrome.

Treatment of Wam- A Study of One Hundred and Six Cases.

One hundred and six cases comprising different of warts were included the study. The types of treatment tried were topical systemic and physical. Podophylin 25% in tincture benzoin co was very effective for genital warts, while electrocautery was successful in 87% cases of common warts. Systemic medication such as levamisole and thuja-200 did not give satisfactory results.

Dermatofibrosarcoma Protuberans.

A 29-year-old male developed dermatofibrosarcoma protuberans over the thigh. It was large, multi-nodular and asymptomatic.