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A compact sensory platform has been fabricated using a graphene field effect transistor (GFET) to identify the biomolecules by pH sensing. The monolayer GFET is driven by an in-built top-gate for detecting the pH of the contacting buffer solution. The GFET device detects the effect of hydroxide ions on a graphite surface. Electrical characteristics of the device were measured after desiccating the buffer solution on the surface of the monolayer graphene. Electrically, the VDirac point shifted toward the positive direction when the pH value of the buffer solution is varied. The transfer curve of the device also moved in the positive direction with increasing pH values, indicating charge transfer from dopant molecules to the surface of graphene. The sensitivity of the device was estimated to be ~48.5 mV/pH. The fabrication of the compact GFET device with an in-built gate provides a platform for effective pH sensing with a user-friendly interface for biosensing applications.

Wastewater treatment plants are considered as hotspots of emerging antimicrobial genes and mobile genetic elements. We used a shotgun metagenomic approach to examine the wide-spectrum profiles of ARGs (antibiotic resistance genes) and MGEs (mobile genetic elements) in activated sludge samples from two different hospital trains at the wastewater treatment plants (WWTPs) in Daegu, South Korea. The influent activated sludge and effluent of two trains (six samples in total) at WWTPs receiving domestic sewage wastewater (SWW) and hospital wastewater (HWW) samples collected at multiple periods were subjected to high throughput 16S rRNA metagenome sequencing for microbial community diversity. Cloacibacterium caeni and Lewinella nigricans were predominant in SWW effluents, while Bacillus subtilis and Staphylococcus epidermidis were predominant in HWW effluents based on the Miseq platform. Totally, 20,011 reads and 28,545 metagenomic sequence reads were assigned to 25 known ARG types in the SWW2 and HWW5 samples, respectively. The higher abundance of ARGs, including multidrug resistance (>53%, MDR), macrolide-lincosamide-streptogramin (>9%, MLS), beta-lactam (>3.3%), bacitracin (>4.4%), and tetracycline (>3.4%), confirmed the use of these antibiotics in human medicine. In total, 190 subtypes belonging to 23 antibiotic classes were detected in both SWW2 and HWW5 samples. RpoB2, MacB, and multidrug (MDR) ABC transporter shared the maximum matched genes in both activated sludge samples. The high abundance of MGEs, such as a gene transfer agent (GTA) (four times higher), transposable elements (1.6 times higher), plasmid related functions (3.8 times higher), and phages (two times higher) in HWW5 than in SWW2, revealed a risk of horizontal gene transfer in HWW. Domestic wastewater from hospital patients also influenced the abundance of ARGs and MGEs in the activated sludge process.

Neurodegenerative diseases are heterogeneous group of diseases characterized by the progressive damage to the structure and functions of the components of central nervous system (CNS) and/or the peripheral nervous system (PNS). Millions of people are affected worldwide by various types of neurodegenerative diseases, among which Alzheimer’s disease (AD) and Parkinson’s disease (PD) are the most common types. Other neurodegenerative diseases are Huntington’s disease (HD), motor neuron disease (MND), spinocerebellar ataxia (SCA), spinal muscular atrophy (SMA), and prion disease. The etiopathogenesis of most of these diseases is unknown. However, extensive research on neurochemistry and neurotransmitters has contributed significantly to the exploration of pathophysiological mechanisms of NDs. In this chapter, the underlying pathological mechanism behind the most common neurodegenerative disease, i.e., Alzheimer’s disease, has been discussed based on the recent scientific data.

The challenges faced during starting of an aircraft gas turbine engine using a Jet Fuel Starter (JFS) at high altitude airbase are discussed in this paper. Autonomous ground starts at high altitude airbase in soaked sub-zero temperature condition without any external ground support assistance is a challenge. Generally, the start cycle (sub-idle speed) at sub-zero temperatures of a gas turbine engine at high altitudes is influenced by several factors. Drag loads are estimated due to change in lube oil viscosity of engine gearbox and accessory gear box that affects available torque margin of a starter. These estimated loads are superimposed on starter characteristics to identify the available margins for successful starts. The cold start is particularly severe, since it increases the tip clearance between rotor and casing of the engine due to difference in its thermal growth. Higher tip clearances significantly degrade compressor surge margin and results in rotating stall. Inconsistent engine starts were resolved by adopting alternative methods without any change in hardware. This paper presents set of methods used to overcome inconsistent engine starts at high altitude cold weather conditions.

Giant intracranial aneurysms, and aneurysms in the posterior circulation of the brain, are each rare entity when considered separately. It is more uncommon to find both coexisting. Aneurysms usually present when they rupture and haemorrhage, and for one to present with non-haemorrhagic symptoms, is rarer. The authors present an unusual case of a giant aneurysm of the anterior inferior cerebellar artery masquerading as a cerebellopontine angle tumour with cerebellar signs. The patient was treated with a retromastoid suboccipital craniectomy and microsurgical clipping and excision, with excellent results. A PubMed search of existing literature was carried out and reviewed and has been discussed.

Background Malaria remains an important cause of morbidity and mortality in India. Though many comprehensive studies have been carried out in Africa and Southeast Asia to characterize and examine determinants of Plasmodium falciparum and Plasmodium vivax malaria pathogenesis, fewer have been conducted in India. Methods A prospective study of malaria-positive individuals was conducted at Goa Medical College and Hospital (GMC) from 2012 to 2015 to identify demographic, diagnostic and clinical indicators associated with P. falciparum and P. vivax infection on univariate analysis. Results Between 2012 and 2015, 74,571 febrile individuals, 6287 (8.4%) of whom were malaria positive, presented to GMC. The total number of malaria cases at GMC increased more than two-fold over four years, with both P. vivax and P. falciparum cases present year-round. Some 1116 malaria-positive individuals (mean age = 27, 91% male), 88.2% of whom were born outside of Goa and 51% of whom were construction workers, were enroled in the study. Of 1088 confirmed malaria-positive patients, 77.0% had P. vivax, 21.0% had P. falciparum and 2.0% had mixed malaria. Patients over 40 years of age and with P. falciparum infection were significantly (p

Self-loosening of fastened systems is known as a severe damage mechanism besides the loss of preload due to relaxation and as a result of this the failure of the joint. Main problem is, that self-loosening mostly leads to a rapid preload loss when occurs. In the 1970s first systematic investigations due to this are reported from Junker et al. using a transverse-vibrational test stand [13]. Nowadays numeric calculation approaches are available (e.g. [12]). All approaches show that very small displacements from loading before complete sliding are sufficient to induce self-loosening — which is a screw rotation against its tightening direction without material rupture of the screw. Today the mechanism of self-loosening under uni-axial transverse load of single-screwed joints with plain bearing surface is understood and predictable. Also combined loads of vibration and rotation became the focus of university-based research. The challenge is to transfer the knowledge about the mechanism to component fastened systems with multi-screw joints. The fundamental mechanism is not sufficient for component design. This is the reason why up to now no prediction in advance is established in guidelines. First, this paper shows the time-sequence of self-loosening in general with its different stages. The second step is to work out important influences on self-loosening which will be shown by existing calculations. Then a stress-based calculation and a better criterion for self-loosening will be developed. Next step, if analytics come to their limits, is the numeric simulation of system behavior. With this the critical preload for self-loosening must be determined to ensure safety of the connection. Following from this screw joints can be dimensioned without risk of self-loosening. The simulation procedure includes right modelling with boundary conditions as well as defining evaluation procedure for a ‘self-loosening-safety-margin’. With simulation of a single-screw joint it gets clear that either analytical or numerical approach can be used. But already for two screws in a fastened system the limits of known equations become obvious. Finally, results of a vibrational test are shown before conclusions and outlook.

Biometrics authentication is an effective method for automatically recognizing a person’s identity with high confidence. Multispectral palm print biometric system is relatively new biometric technology and is in the progression of being endlessly refined and developed. Multispectral palm print biometric system is a promising biometric technology for use in various applications including banking solutions, access control, hospital, construction, and forensic applications. This paper proposes a multispectral palm print recognition method with extraction of multiple features using kernel principal component analysis and modified finite radon transform. Finally, the images are classified using Local MeanK-Nearest Centroid Neighbor algorithm. The proposed method efficiently accommodates the rotational, potential deformations and translational changes by encoding the orientation conserving features. The proposed system analyses the hand vascular authentication using two databases acquired with touch-based and contactless imaging setup collected from multispectral Poly U palm print database and CASIA database. The experimental results clearly demonstrate that the proposed multispectral palm print authentication obtained better result compared to other methods discussed in the literature.