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This paper investigates the integration of optical fibers into an on-chip Fabry–Pérot (FP) resonator to achieve high-quality (Q) factors, which is favorable in sensing applications. Initially designed for high-speed data transmission, optical fibers are now utilized in sensing applications because of their flexibility and sensitivity to optical phenomena. This article focuses on the role of single-mode fibers (SMF) and the geometry of different structures in enhancing light confinement within FP resonators. Two distinct on-chip designs utilizing SMFs are demonstrated, modeled, and experimentally evaluated. One achieves a Q-factor higher than 5200, demonstrating significant improvement in light confinement, while the other maximizes the spectral range between the resonant modes’ peaks, maximizing the sensing range through the wavelength shift. This is supported by visualized simulation and coupling efficiencies calculations for fundamental and higher-order modes for comprehensive analysis. Comparison with existing literature is also made, underscoring the advancements achieved by the presented approaches. The findings contribute to the development of microscale refractive index sensing applications, highlighting the vital role of optical fiber integration for high-performance sensing.

Abstract Perfect absorbers can be used in photodetectors, thermal imaging, microbolometers, and thermal photovoltaic solar energy conversions. The spectrum of Mid-infrared (MIR) wavelengths offers numerous advantages across a wide range of applications. In this work, we propose a fractal MIR broadband absorber which is composed of three layers: metal, dielectric, and metal (MDM), with the metal being considered as n-type doped silicon (D-Si) and the dielectric is silicon carbide (SiC). The architectural design was derived from the Sierpinski carpet fractal, and different building blocks were simulated to attain optimal absorption. The 3D finite element method (FEM) approach using COMSOL Multiphysics software is used to obtain numerical results. The suggested fractal absorber exhibits high absorption enhancement for MIR in the range between 3 and 9 µm. D-Si exhibits superior performance compared to metals in energy harvesting applications that utilize plasmonics at the mid-infrared range. Typically, semiconductors exhibit rougher surfaces than noble metals, resulting in lower scattering losses. Moreover, silicon presents various advantages, including compatibility with complementary metal–oxide–semiconductor (CMOS) and simple manufacturing through conventional silicon fabrication methods. In addition, the utilization of doped silicon material in the mid-IR region facilitates the development of microscale integrated plasmonic devices.

Hand hygiene is the key factor to control and prevent the spread of infections, for example, hospital-acquired infections (HAIs). People commonly use alcohol-based hand sanitizers to assure hand hygiene. However, frequent use of alcohol-based hand sanitizers in a pandemic situation (e.g., COVID-19) was associated with serious drawbacks such as skin toxicity including irritation, skin dermatitis, and skin dryness or cracking, along with peeling, redness, or itching with higher possibility of infection. This demands the development of alternative novel products that are effective as alcohol-based hand sanitizers but have no hazardous effects. Zinc oxide nanoparticles (ZnO-NPs) are known to have broad-spectrum antimicrobial activity, be compatible with the biological system and the environment, and have applicable and economic industrial-scale production. Thus, ZnO-NPs might be a good candidate for hand sanitation. To the best of our knowledge, the antibacterial activity of ZnO-NPs in comparison to alcohol-based hand sanitizers has not yet been studied. In the present work, a comparative study of the antibacterial activity of ZnO-NPs vs. Sterillium, a commercial alcohol-based hand sanitizer that is commonly used in Egyptian hospitals, was performed against common microorganisms known to cause HAIs in Egypt, including Acinetobacter baumannii, Klebsiella pneumoniae, Methicillin-resistant Staphylococcus aureus (MRSA), and Staphylococcus aureus. The safety profiles of ZnO-NPs and Sterillium were also assessed. The obtained results demonstrated the superior antibacterial activity and safety of ZnO-NPs compared to Sterillium. Therefore, ZnO-NPs could be a promising candidate for hand sanitation in comparison to alcohol-based hand sanitizers; however, several studies related to long-term toxicity and stability of ZnO-NPs and investigations into their antimicrobial activity and safety in healthcare settings are still required in the future to ascertain their antimicrobial activity and safety.

Hand hygiene is considered to be the key factor in controlling and preventing infection, either in hospital care settings or in the community. Alcohol-based hand sanitizers are commonly used due to their rapid action and broad spectrum of microbicidal activity, offering protection against bacteria and viruses. However, their frequent administration during COVID-19 pandemic was associated with serious hazards, such as skin toxicity, including irritation, skin dermatitis, skin dryness or cracking, along with peeling redness or itching, with the higher possibility of getting infections. Thus, there is a need to find alternative and novel approaches for hand sanitation. In our previous publications, we reported that rhamnolipids nano-micelles had a comparable antibacterial activity to alcohol-based hand sanitizer and a lower cytotoxicity against human dermal fibroblast cells. In the current study, we investigated the antiviral activity of rhamnolipids nano-micelles against SARS-CoV-2. There was no cytotoxic effect on Vero cells noted at the tested concentrations of rhamnolipids nano-micelles. The rhamnolipids nano-micelles solution at 20, 78, and 312 µg/mL all demonstrated a significant (p < 0.05) decrease of virus infectivity compared to the virus only and the blank vehicle sample. In addition, an acute irritation test was performed on rabbits to further ascertain the biosafety of rhamnolipids nano-micelles. In the eye and skin irritation tests, no degree of irritation was recorded after topical application of rhamnolipids nano-micelles. In addition, histopathological, biomarker, and hematological analyses from animals treated with rhamnolipids nano-micelles were identical to those recorded for untreated animal. From the above, we can conclude that rhamnolipids nano-micelles are a good candidate to be used as a hand sanitizer instead of alcohol-based hand sanitizers. However, they must still be tested in the future among healthcare workers (HCW) in a health care setting to ascertain their antimicrobial efficacy and safety compared to alcohol-based hand sanitizers.

Emphysematous cholecystitis is an uncommon and dangerous complication of acute cholecystitis. Common risk factors for this disease include male gender, old age, presence of diabetes mellitus and cholelithiasis. The disease is best treated with emergent surgery and parenteral antibiotics. We present the case of an 85-year-old nursing home resident who presented to our institution with a 3-day history of gradually worsening abdominal discomfort.

Primary malignant melanoma of the anus and rectum is a rare and aggressive neoplasm that tends to invade locally and metastasize early in the course of the disease. It is often misdiagnosed as hemorrhoids or as one of the other benign anorectal conditions and is thus linked to an overall poor prognosis and a 5-year survival rate of less than 20%. Optimal treatment is still controversial, and current evidence does not show any preferential survival benefit from abdominoperineal resection over wide local excision. Chemotherapy or radiotherapy may be used for advanced disease. We report a 71-year-old female presenting with painful bowel movements and blood in stools. She was eventually found to have a mass arising from the anorectal junction with regional lymph node involvement. The patient underwent an abdominoperineal resection and is currently scheduled for chemotherapy.

Radiation therapy has a solid role in the management of breast adenocarcinoma. It significantly reduces the rates of disease recurrence. Nevertheless, radiation therapy is not without side effects and patients who have undergone breast irradiation are at increased risk for lung disease, sarcomas, acute leukemia and esophageal cancer. We present a case of radiation-induced breast osteosarcoma 29 years after radiation therapy and lumpectomy for breast adenocarcinoma. The patient had several disease recurrences after surgical resection and was found to have pulmonary metastases.

Leukocytoclastic vasculitis (LCV) is a small-vessel vasculitis with a reported incidence rate of 30 cases per million persons per year. It usually presents as a palpable purpuric skin rash on legs, though any part of the body can be affected. LCV rash may have an associated burning sensation or pain and in some cases may involve internal organs. In some cases, LCV rash may present as nodules, recurrent ulcerations or asymptomatic lesions. The diagnosis of LCV is usually made on skin biopsy. Etiological triggers may not be identified in as many as half of the cases. Treatment is usually conservative and includes identification and removal or treatment of the etiological trigger except in cases with internal organ involvement where systemic steroids and immunosuppressant may be necessary. In this article we present a case of indomethacin-associated LCV that improved with discontinuation of the offending agent.

Ovarian cancer is the second most common gynecological cancer in the Western world. Despite a good response to treatment, most patients with ovarian cancer will relapse. The abdominal, pelvic, and retroperitoneal cavities represent the most common sites of ovarian cancer recurrence, with inguinal lymph node involvement rarely reported. Herein we report the case of a 48-year-old Caucasian female who underwent successful surgical and chemotherapy treatment for ovarian epithelial cancer. Two years later, the patient was found to have painless left inguinal adenopathy, which was subsequently found to be metastatic ovarian cancer. CA-125 levels were elevated despite the lack of any foci of metabolically active tissue on imaging. Inguinal lymph node involvement is a rare sign of ovarian cancer. Despite that, it is essential to consider ovarian cancer in the differential diagnosis for inguinal lymphadenopathy in a female patient.

Propofol infusion syndrome is a rare but extremely dangerous complication of propofol administration. Certain risk factors for the development of propofol infusion syndrome are described, such as appropriate propofol doses and durations of administration, carbohydrate depletion, severe illness, and concomitant administration of catecholamines and glucocorticosteroids. The pathophysiology of this condition includes impairment of mitochondrial beta-oxidation of fatty acids, disruption of the electron transport chain, and blockage of beta-adrenoreceptors and cardiac calcium channels. The disease commonly presents as an otherwise unexplained high anion gap metabolic acidosis, rhabdomyolysis, hyperkalemia, acute kidney injury, elevated liver enzymes, and cardiac dysfunction. Management of overt propofol infusion syndrome requires immediate discontinuation of propofol infusion and supportive management, including hemodialysis, hemodynamic support, and extracorporeal membrane oxygenation in refractory cases. However, we must emphasize that given the high mortality of propofol infusion syndrome, the best management is prevention. Clinicians should consider alternative sedative regimes to prolonged propofol infusions and remain within recommended maximal dose limits.

Tumor lysis syndrome (TLS) is a potentially deadly complication of tumors or their treatment. This syndrome consists of a constellation of laboratory findings such as hyperuricemia, hyperkalemia, hyperphosphatemia, and hypocalcemia, known as laboratory TLS. When clinical complications such as seizures, acute renal failure, and cardiac dysrhythmias occur in patients with laboratory TLS, the syndrome is called clinical TLS. TLS is especially common in patients with hematological malignancies with rapid cellular turnover rates such as acute lymphocytic leukemia and Burkitt lymphoma, but is very rare in patients with solid tumors. Nevertheless, there are multiple reports in the literature on the occurrence of TLS in patients with solid tumors. In this review article, we summarize the current data on the occurrence of TLS in patients with solid tumors. We propose an algorithm of risk stratification and prevention of TLS in patients with solid cancers.

Cardiac arrest is a true medical emergency and clinicians should base the management on American Heart Association advanced cardiac life support algorithm. The potential triggers of cardiac arrest should be sought. We present a case of a 27-year-old female who developed cardiac arrest and was later found to have congenital long QT syndrome. The patient’s outcome was favorable. Discussion of the key management options will be discussed in the text.

Chest pain is one of the most common reasons for emergency department visits. Emergency medicine doctors should focus their initial assessment on patients’ stability. History, physical examination, and ancillary testing should exclude serious causes such as acute coronary syndrome, acute aortic syndromes, pulmonary embolism, pneumothorax, esophageal perforation, and rupture as well as pericardial tamponade. Young age should not be used alone as a predictor of a benign condition. Below we present a case of a 24-year-old female who was found to have ascending aortic dissection and was sent for emergent surgery.

Papillary serous carcinoma of the uterine cervix is a rare histological variant of cervical adenocarcinoma, with a very small number of cases reported. It is an aggressive tumor and is usually diagnosed at advanced stages by the time of diagnosis. Early-stage tumors can be treated with surgery and/or radiotherapy, while late-stage tumors have been treated with chemotherapy plus radical surgery with intermittent success. Here we report a case of metastatic papillary serous carcinoma observed at our hospital, which has been treated with debulking surgery and combination chemotherapy with carboplatin and paclitaxel.

Patients with nephrotic syndrome are at an increased risk for thrombotic events; deep venous thrombosis, renal vein thrombosis, and pulmonary embolism are quite common in patients with nephrotic syndrome. It is important to note that nephrotic syndrome secondary to membranous nephropathy may impose a greater thrombotic risk for unclear reasons. Increased platelet activation, enhanced red blood cell aggregation, and an imbalance between procoagulant and anticoagulant factors are thought to underlie the excessive thrombotic risk in patients with nephrotic syndrome. The current scientific literature suggests that patients with low serum albumin levels and membranous nephropathy may benefit from primary prophylactic anticoagulation. A thorough approach which includes accounting for all additional thrombotic risk factors is, therefore, essential. Patient counseling regarding the pros and cons of anticoagulation is of paramount importance. Future prospective randomized studies should address the question regarding the utility of primary thromboprophylaxis in patients with nephrotic syndrome.

Hairy cell leukemia is a rare lymphoid neoplasm arising from mature B-lymphocytes. Clinically, the disease presents with splenomegaly and abdominal discomfort, frequent infections, fatigue and bleeding because of related cytopenias. Bone marrow biopsy is essential for diagnosis. Below we describe a case of a 70-year-old African-American male who presented to our hematology clinic complaining of fatigue. Clinical exam and computed tomography imaging did not reveal splenic enlargement. Blood work-up revealed pancytopenia and bone marrow was diagnostic for hairy cell leukemia.The patient was started on cladribine, with gradual improvement of his symptoms and blood count abnormalities. Therefore, it is essential to keep hairy cell leukemia in the differential of pancytopenia even in the absence of a splenomegaly.

Primary colorectal lymphoma is a rare malignancy accounting for 3% of all gastrointestinal lymphomas and 0.1-0.5% of all colorectal malignancies. Among primary colorectal lymphomas, the most common histological subtype of colorectal lymphoma is diffuse large B-cell lymphoma. We report a case of an 84-year old Caucasian female who was admitted to the hospital because of a 2 days history of altered mental status. In the emergency department the patient was found to have acute kidney injury and hypercalcemia. On physical examination a large lower quadrant abdominal mass was palpated. Computed tomography scan of abdomen confirmed the presence of a mass along the cecum and proximal ascending colon. Colonoscopy showed a large ulcerated mass and biopsy was consistent with diffuse large B-cell lymphoma. The patient underwent colectomy but refused to receive chemotherapy.

Drug-induced immune hemolytic anemia is a rare condition with an incidence of 1 per million of the population. We report the case of a 36-year-old female who presented to the emergency department complaining of shortness of breath and dark colored urine. Physical examination was significant for pale mucous membranes. The patient reported using ibuprofen for a few days prior to presentation. Complete blood count performed before starting ibuprofen revealed normal platelets and hemoglobin values. On admission, the patient had evidence of hemolytic anemia with hemoglobin of 4.9 g/dL, hematocrit of 14.2%, lactate dehydrogenase 435 IU/L, and reticulocytosis 23.2%. Further testing ruled out autoimmune disease, lymphoma, and leukemia as etiologies for the patient’s new onset hemolytic anemia. Ibuprofen was immediately stopped with a gradual hematologic recovery within 3 days.

Acute postpartum dyspnea in a young, previously healthy adult encompasses numerous conditions. One should be aware of various differential diagnoses including delayed postpartum preeclampsia-induced pulmonary edema where the occurrence is rare but a significant one due its deleterious consequences. We report a case of 26-year-old gravida 1/para 1 female who presented to the hospital with progressive dyspnea after 1 week of normal spontaneous vaginal delivery. On physical examination, her blood pressure was severely elevated. Her clinical signs and symptoms were consistent with pulmonary edema, but diagnostic tests excluded the cardiogenic causes. Further test revealed proteinuria. The patient was diagnosed with delayed postpartum preeclampsia.

A 17-year-old Hispanic female presented to our hospital with complaints of right upper quadrant abdominal pain, vomiting, and fever. Physical exam was positive for hepatomegaly. Abdominal computed tomography showed multiple hypoechoic liver masses. Liver biopsy was done, which was diagnostic for hepatic epithelioid hemangioendothelioma.

The estimated annual incidence for drug-induced thrombocytopenia is 10 per million. Although fatal consequences are uncommon, life-threatening hemorrhage can occur due to spontaneous bleeding. We report a case of 84-year-old Caucasian female who presented to the emergency department with multiple episodes of bloody bowel movements. One week prior to this admission, she was started on trimethoprim-sulfamethoxazole for the treatment of skin abscess. On admission laboratory results showed platelet count of 4 × 103/mm3 and hemoglobin of 10.2 g/dL. Because of unstable vital signs, the patient was transferred to the intensive care unit where she received multiple units of platelet and blood transfusion. Drug-induced thrombocytopenia due to TMP/SMX was suspected. Intravenous methylprednisolone was started as well as immune globulin with good clinical response.

Chronic back pain is a common presenting complaint that is frequently encountered by clinicians. The challenge for clinicians is identifying the relatively few patients with a significant probability of a more serious problem that requires further evaluation. Such individuals require further evaluation for possible occult malignancy, infection, or fracture. We present a case of a 50-year-old male with a past medical history of chronic back pain and IV drug abuse who presented with acute back pain and in whom a diagnosis of vertebral osteomyelitis was missed during multiple visits to the emergency room.

A 52-year-old male with no significant past medical history reports increasing generalized fatigue and weakness for the past 2 weeks. Physical examination reveals jaundice and pallor without organomegaly or lymphadenopathy. His hemoglobin was 5.9 g/dL with a mean corpuscular volume of 87.1 fL and elevated red blood cell distribution width of 30.7%. His liver function test was normal except for elevated total bilirubin of 3.7 mg/dL. Serum LDH was 701 IU/L, and serum haptoglobin was undetectable. Further investigation revealed serum vitamin B12 of