Abstract
This letter presents a new thin substrate‐integrated waveguide with twisted integrated–digitated capacitor‐based corrugations that offers a transmission loss < 0.55 dB. The presented ...waveguide operates at TE
10
mode and is used to present a wideband beam‐scanning leaky‐wave antenna with an array of dumbbell‐shaped slots. The antenna is shown to operate at a frequency band of 25–37 GHz and offers a gain > 13 dBi throughout the frequency band. It has a frequency‐dependent beam‐scanning capability of 6 deg/GHz. The proposed antenna being thin is extremely conformal and is suitable for applications in millimetre‐wave off‐body communication.
A solution processed top-contact bottom-gated SnO
2
thin-film transistor (TFT) has been fabricated using a TiO
2
/Li–Al
2
O
3
bilayer stacked gate dielectric that show operating voltage of this TFT ...within 2.0 V. It is observed that the bilayer dielectric has much higher areal capacitance with lower leakage current density that significantly improve the overall device performance of TFT. The TFT with bilayer gate dielectric shows an effective carrier mobility (
μ
sat
) of 9.2 cm
2
V
−1
s
−1
with an on/off ratio of 7.1 × 10
3
which are significantly higher with respect to the TFT with a single layer Li–Al
2
O
3
gate dielectric. The origin of this improvement is due to the Schottky junction between the highly doped silicon (p
++
-Si) and TiO
2
of bilayer stacked dielectric that induced electrons to the channel which reduces the dielectric/semiconductor interface trap-state. This investigation opens a new path to develop TFT device performance using a suitable bilayer stack of gate dielectric.
Solar air heating devices have been employed in a wide range of industrial and home applications for solar energy conversion and recovery. It is a useful technique for increasing the rate of heat ...transfer by artificially creating repetitive roughness on the absorbing surface in the form of semicircular ribs. A thermo-hydraulic performance analysis for a fully developed turbulent flow through rib-roughened solar air heater (SAH) is presented in this article by employing computational fluid dynamics. Both 2-dimensional geometrical modeling and numerical solutions were performed in the finite volume package ANSYS FLUENT. The renormalization-group (RNG) k-ε turbulence model was used, as it is suitable for low Reynolds number (Re) turbulent flows. A thermo-hydraulic performance analysis of an SAH was carried out for a ranging Re, 3800–18,000 (6 sets); relative roughness pitch (RRP), 5–25 (12 sets); relative roughness height (RRH), 0.03–0.06 (3 sets); and heat flux, 1000 W/m2. The numerical analysis revealed that with an RRP of 5 and an RRH of 0.06, the roughened duct produces the highest augmentation in average Nur in the order of 2.76 times that of a plain duct at an Re of 18,000. With an RRP = 10 and RRH = 0.06, the roughened duct was found to provide the most optimum thermo-hydraulic performance parameter (THPP). The THPP was determined to have a maximum value of 1.98 when the Re is equal to 15,000. It was found that semi-circular ribs which have a rib pitch = 20 mm and a rib height = 2 mm can be applied in an SAH to enhance heat transfer.
The medieval period Ahom dynasty which ruled Assam in North-East India from 13th to 19th century CE has unique Moidams (or Maidams) built all across the upper Brahmaputra valley in Assam. The Moidams ...and history of Ahom rulers with reference to their relationship with landscape of the region has been scantily studied till date. The Moidams were built on piedmont to alluvial zone of the colluvial deposits of the Naga Thrust, located in the North-East part of Assam in India. The transit of Ahom rulers from Yunnan (China borderlands to Charaideo, Assam, India), where the Ahoms established their first capital, via Burma (Myanmar) and Nagaland showcases a unique historical account of the region. The lifestyle, practices and the quest for newer land of the Ahoms, which would justify their long-term occupational goals, also highlighted their understanding of climate, tectonics and man-environment relationships. The architecture of Moidams and their sitting at the piedmont at Charaideo is unique in terms of their long-standing history of 600 years in the face of natural wrath of disasters like earthquakes and seasonal floods. Based upon detailed investigation and assessment carried out by several researchers for geoheritage sites and geoarcheosites, the Moidams at Charaideo, best exemplifies. The Moidam sites warrants detailed geological, geophysical and botanical investigation aspects for illuminating its rich cultural history in light of man-environment / anthropological landscape characteristics.
BACKGROUND: Dry eye disease is a multifactorial ocular surface disease that causes symptoms of vague ocular pain, discomfort, grittiness, burning sensation, itching, and redness in the eyes. It is ...one of the most common disorders of the eye which is often underrecognized and can significantly affect the quality of life of patients.
OBJECTIVES: The objective of this study is to assess how often postmenopausal women have dry eyes and to evaluate the relationship between dry eye disease and age in postmenopausal women.
MATERIALS AND METHODS: During 3 months, postmenopausal women who attended the ophthalmology outpatient department at a tertiary level hospital participated in a hospital-based cross-sectional study. Four hundred postmenopausal women were conveniently selected as the sample. To identify the existence of dry eyes, Schirmer's test was performed.
RESULTS: The study population's average age was 59.09 ± 8.46 years. In the research, the average age of menopause onset was 47.68 ± 2.67 years. Dry eye condition was found to be 39.75% prevalent. The vast majority of individuals with dry eye illness had moderate dry eyes (18.25%). Dry eyes became more common with age, which was statistically significant.
CONCLUSION: The findings of the current study have shown that many postmenopausal women experience dry eye disease. The study emphasizes the value of routine eye examination for postmenopausal women to identify dry eye problems early, receive the proper treatment, and help these women improve their quality of life.
Exosomes, a subtype of the class of extracellular vesicles and nano-sized particles, have a specific membrane structure that makes them an alternative proposition to combat with cancer through slight ...modification. As constituents of all most all the primary body fluids, exosomes establish the status of intercellular communication. Exosomes have specific proteins/mRNAs and miRNAs which serve as biomarkers, imparting a prognostic tool in clinical and disease pathologies. They have efficient intrinsic targeting potential and efficacy. Engineered exosomes are employed to deliver therapeutic cargos to the targeted tumor cell or the recipient. Exosomes from cancer cells bring about changes in fibroblast via TGFβ/Smad pathway, augmenting the tumor growth. These extracellular vesicles are multidimensional in terms of the functions that they perform. We herein discuss the uptake and biogenesis of exosomes, their role in various facets of cancer studies, cell-to-cell communication and modification for therapeutic and diagnostic use.
Introduction Pregnancy-induced hypertension (PIH) is a hypertensive disorder in pregnancy that occurs after 20 weeks of pregnancy in the absence of previously known hypertension. PIH is a common and ...serious complication accompanying pregnancy. Pre-eclampsia and eclampsia are multisystem disorders that can involve end organs like kidneys, liver, eyes, haematopoietic system and placenta. Though ocular involvement is not uncommon in PIH, ocular examination is not always done in all cases of PIH. Timely detection of changes in retinal vasculature can be a hint to the underlying changes in the vascular system of the various end organs of the human body including placental circulation. Adequate management of PIH is very important for both fetal and maternal well-being. Aim To evaluate the ocular manifestations in women affected by PIH (mild pre-eclampsia, severe pre-eclampsia and eclampsia) presenting to a tertiary-level hospital. Methodology This was a hospital-based cross-sectional study carried out for a period of one year at a tertiary-level hospital. A total of 120 subjects diagnosed as cases of pre-eclampsia/eclampsia admitted to the eclampsia ward of the obstetric unit formed the study population. After taking history, a detailed ocular examination was done for all patients and the findings were noted. Results The mean age of the study population was 31.91 ± 4.38 years (range 21 to 39 years). The mean gestational age was 30.89 ± 3.98 weeks. Fifty-three (44.17%) were primigravida, 64 (53.33%) were multiparous, and three (2.5%) were grand multiparous. Sixty-two (51.67%) had mild pre-eclampsia, 50 (41.67%) had severe pre-eclampsia and eight (6.67%) had eclampsia. The mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) recorded in the study were 155.32 ± 11.89 mmHg and 104.3 ± 11.41 mmHg respectively. Ocular symptoms were present in 43 (35.83%) participants. Blurring of vision (19.17%) was the commonest ocular symptom observed in the study population followed by photopsia (13.33%), diplopia (9.17%), intermittent loss of vision (5.83%), ocular pain (6.67%), and scotoma (1.67%). Systemic symptoms included headache (11.67%), epigastric pain (3.33%), and nausea (5%). Anterior segment findings like conjunctival congestion, lid edema, and subconjunctival hemorrhage each accounted for 1.67% of the study population. Fundal changes were present in 33.33% of cases. Arteriolar narrowing was the commonest fundal finding amounting to 15.83%, followed by arteriovenous (AV) crossing changes also in 15.83%, cotton wool spots in 5.83%, retinal haemorrhages in 8.33%, papilledema in 2.5%, and choroidal infarcts in 1.67% participants. Grade 1 hypertensive retinopathy was observed in 15.83% of participants, grade 2 in 8.33% of participants, grade 3 in 6.67% of participants and grade 4 in 2.5% of participants. The mean SBP and mean DBP were high among those with fundal changes (163.35 ± 10.25 mmHg and 111.15 ± 10.29 mmHg) compared to those without fundal changes (151.3 ± 10.58 mmHg and 100.88 ± 10.41 mmHg). This was statistically significant. Proteinuria showed significant correlation with retinal changes. Conclusion The retinal vasculature changes correlate with the severity of hypertension, hence, it is very important to seek ophthalmologic opinion for evaluation, diagnosis and prompt management of PIH.
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