27 research outputs found
130 nm low power CMOS analog multiplier
Processing analog signal often involves analog multiplier and the multiplier is part of system on chip (SoC). Designing such system with a low power consumption is crucial nowadays. It is very important to increase the system battery lifetime. The design also must be smaller in size. In order to reduce the power consumption of the multiplier, an architecture that require smaller current must be designed and the approach is to use a design that is able to function at a low voltage supply. This project has designed the analog multiplier with a low power consumption using Silterra 130 nm Complementary Metal Oxide Semiconductor (CMOS) technology. A four quadrant technique is applied in the design. The scaling of transistor will help in reducing the size of the analog multiplier, and the proposed circuit architecture has produced a compact multiplier. Cadence electronic design automation (EDA) Tools is used to design the circuit. The schematic, layout, physical verification and parasitic extraction with post layout simulation are done to verify the multiplier circuit is functioning. The analog multiplier is operated with 1.2 V voltage supply and the power consumption is 98 μW. At 1 V, the power consumption is 32 μW. The total area for the design is 99 μm²
Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study
Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk
Effectiveness of probiotics in the prevention of carious lesions during treatment with fixed orthodontic appliances.
Prospective, multicentre study of screening, investigation and management of hyponatraemia after subarachnoid haemorrhage in the UK and Ireland
Background: Hyponatraemia often occurs after subarachnoid haemorrhage (SAH). However, its clinical significance and optimal management are uncertain. We audited the screening, investigation and management of hyponatraemia after SAH. Methods: We prospectively identified consecutive patients with spontaneous SAH admitted to neurosurgical units in the United Kingdom or Ireland. We reviewed medical records daily from admission to discharge, 21 days or death and extracted all measurements of serum sodium to identify hyponatraemia (<135 mmol/L). Main outcomes were death/dependency at discharge or 21 days and admission duration >10 days. Associations of hyponatraemia with outcome were assessed using logistic regression with adjustment for predictors of outcome after SAH and admission duration. We assessed hyponatraemia-free survival using multivariable Cox regression. Results: 175/407 (43%) patients admitted to 24 neurosurgical units developed hyponatraemia. 5976 serum sodium measurements were made. Serum osmolality, urine osmolality and urine sodium were measured in 30/166 (18%) hyponatraemic patients with complete data. The most frequently target daily fluid intake was >3 L and this did not differ during hyponatraemic or non-hyponatraemic episodes. 26% (n/N=42/164) patients with hyponatraemia received sodium supplementation. 133 (35%) patients were dead or dependent within the study period and 240 (68%) patients had hospital admission for over 10 days. In the multivariable analyses, hyponatraemia was associated with less dependency (adjusted OR (aOR)=0.35 (95% CI 0.17 to 0.69)) but longer admissions (aOR=3.2 (1.8 to 5.7)). World Federation of Neurosurgical Societies grade I–III, modified Fisher 2–4 and posterior circulation aneurysms were associated with greater hazards of hyponatraemia. Conclusions: In this comprehensive multicentre prospective-adjusted analysis of patients with SAH, hyponatraemia was investigated inconsistently and, for most patients, was not associated with changes in management or clinical outcome. This work establishes a basis for the development of evidence-based SAH-specific guidance for targeted screening, investigation and management of high-risk patients to minimise the impact of hyponatraemia on admission duration and to improve consistency of patient care
PHOTOCATALYTIC HYDROGEN GENERATION BY ETHANOL ASSISTED WATER SPLITTING REACTION USING MIXED OXIDE OF Ba AND Mn
Visible light active BaMnOx type photocatalyst was synthesized by using sol-gel method. The photocatalyst was characterized by
X- ray diffraction, BET-SA, and UV-visible diffused reflectance spectroscopy (UV-DRS). BaMnOx photocatalyst exhibited an optical band gap
of 2.9 eV with the absorption predominantly in visible region of the light spectrum. The crystallite size of BaMnOx is 24.63 nm as calculated
by the Debye Scherer equation. The BET surface area value for BaMnOx photocatalyst was found to be 16.2 m2/g. The photocatalytic hydrogen
generation was carried out by using Pt as co-catalyst and ethanol as a sacrificial donor. Hydrogen generation was investigated by ethanol
assisted water splitting reaction under visible light irradiation, using a compact glass reactor and tungsten lamp as a source of visible
light. The rate of photocatalytic hydrogen evolution was observed to be 7463 μmol.g-1.h-1 of Pt-BaMnOx
photocatalyst
Synthesis and visible light photocatalytic activity of nanocrystalline PrFeO3 perovskite for hydrogen generation in ethanol–water system
Nanocrystalline PrFeO3 perovskite type orthoferrite was synthesized at 700◦C by using three different
synthesis methods, namely sol–gel, template and combustion method. The synthesized materials were
characterized by XRD, BET-SA, SEM, HRTEM, XPS, FTIR and UV-DRS techniques to understand their
physico-chemical properties. Characterization data reveal the formation of nanocrystalline PrFeO3 perovskite
composition with improved physical properties, possibly due to lower synthesis temperature used. PrFeO3 synthesized
by sol–gel method consists of crystallite size of about 20 nm with absorption maxima at 595 nm
wavelength in visible light range. This photocatalyst shows hydrogen generation of about 2847 μmol.g−1.h−1,
under visible light irradiation in ethanol–water system. The photocatalyst was further investigated for various
operational parameters such as photocatalyst dose variation, illumination intensity, time, etc. in a view to optimize
the hydrogen generation as well as to understand mechanistic aspects. This material appears to follow a
semiconductor type mechanism for ethanol-assisted visible light photocatalyic water-splitting and can also be
an interesting candidate to develop hetero-junction type photocatalysts
Pharmacognostical studies on the root tubers of <i>Asparagus gonoclados</i> Baker –Alternate source for the Ayurvedic drug Shatavari
57-62Asparagus
gonoclados Baker is an important medicinal plant
belonging to the family Liliaceae (sensu
lato). Many species of Asparagus
Linn. including A. gonoclados are
used as substitute of the well known Ayurvedic drug, Shatavari. Root
tubers of Shatavari possesses
adaptogenic, antioxidant, cooling, emollient, diuretic, galactagogue, nervine
tonic, rejuvenating, and stomachic properties; they are useful in treatment of
diseases like diarrhoea, dysentery, dyspepsia, epilepsy, fatigue,
inflammations, nervous disorders, tumours and tuberculosis. The present study
provides taxonomy of the species, pharmacognostical and physico-chemical
details of the root tubers of A.
gonoclados. This helps in
laying down standardisation and pharmacopoeial parameters. Presence of Shatavarin
IV in the alcohol and aqueous extracts is reported in this species for the
first time
Synthesis and visible light photocatalytic activity of nanocrystalline PrFeO 3 perovskite for hydrogen generation in ethanol–water system
Photocatalytic hydrogen generation through water splitting on nano-crystalline LaFeO3 perovskite
Visible light active ABO3 type photocatalyst with LaFeO3 composition was synthesized by
sol-gel method. The photocatalyst was characterized by different techniques such as X-ray
diffraction, BET surface area analysis, particle size analysis, scanning electron microscopy,
UVevisible diffuse reflectance spectroscopy (UVeVisible DRS), and photoluminescence
spectroscopy. LaFeO3 photocatalyst exhibited an optical band gap of 2.07 eV with the
absorption spectrum predominantly in visible region of the spectrum. The BET surface area
of photocatalyst LaFeO3 was observed as 9.5 m2/g, with the crystallite size of 38.8 nm as
calculated by the Debye-Scherer equation. The photocatalytic activity of LaFeO3 was
investigated for hydrogen generation through sacrificial donor assisted photocatalytic
water splitting reaction by varying conditions in feasible parametric changes using visible
light source, ethanol as a sacrificial donor and Pt solution of H2PtCl6 as a co-catalyst. The
rate of photocatalytic hydrogen evolution was observed to be 3315 mmol g�1 h�1 under
optimized conditions and using 1 mg dose of photocatalyst with reaction time of 4 h and
illumination of 400 W