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η-Ricci solitons on Lorentzian -β Kenmotsu manifold are considered an manifolds satisfying certain curvature Conditions, R(,X).S=0, S(,X).R=0, =0,.=0 We proved that in Lorentzian -Kenmotsu manifold (). Then the existence of an -Ricci solitons implies that M is Einstein manifold and if the Ricci curvature tensor satisfies, S(,X).R=0, then Ricci solitons M is steady. If the condition =0, then =0, which shows that is steady.

By 2050, it is predicted that the manufacturing of regular cement for institutional, commercial, and residential structures will spew around 3800 tonnes of carbon dioxide into the atmosphere and use 38% of the world's energy. It has become crucial to create a new class of construction materials that combine eco-friendly, energy-saving, and self-sensing capabilities. Translucent concrete, created through innovation in the material sciences and the fusing of fibre optics and concrete technologies, helps to create structures that are cosier, more artistic, safe, and energy-efficient. The creation of Smart Transparent Concrete, based on its exceptional transparent and smart sensing qualities, is discussed in light of "green" standards and safe evaluation for engineering constructions that have attracted global attention. Dealing with its application and the benefits it offers in the area of smart construction, discover that it can save lighting power consumption, utilise an optical fibre to detect structural stress, and use this concrete as an architectural feature for a pleasing aesthetic sight of the building. Fly ash is used in concrete to explore the partial additional of cement with fly ash. Translucent concrete blocks can be used in many ways and implemented into many be highly advantageous. Keywords: Translucent Concrete, Optical Fiber, Fly Ash, Compressive Strength, Light Transmission.

Trypanosoma evansi is definitely one of the most common pathogenic trypanosomes in all over the world, obviously infecting domestic and wild animals. Before it contributes to even more economic losses, a fast and confirmatory early diagnosis is a must to curb the spread and development of the disease. The current study was aimed to identify Trypanosoma spp. in buffalo blood by blood smear analysis and polymerase chain reaction (PCR) as well as comparison of these two methods. This investigation was performed on 475 buffaloes with anaemia, recurrent fever, muscular weakness and loss of appetite. Out of 475 blood samples, 57 were found anaemic (Hb

Engineering single atomic defects into wide bandgap materials has become an attractive field in recent years due to emerging applications such as solid-state quantum bits and sensors. The simplest atomic-scale defect is the lattice vacancy which is often a constituent part of more complex defects such as the nitrogen-vacancy (NV) centre in diamond, therefore an understanding of the formation mechanisms and precision engineering of vacancies is desirable. We present a theoretical and experimental study into the ultra-fast laser generation of vacancy-interstitial pairs (Frenkel defects) in diamond. The process is described by a set of coupled rate equations of the pulsed laser interaction with the material and of the non-equilibrium dynamics of charge carriers during and in the wake of the pulse. We find that a model for Frenkel defect generation via the recombination of a bound biexciton as the electron plasma cools provides good agreement with experimental data, reproducing an effective non-linearity of $\sim$ 40 for Frenkel defect generation with respect to laser pulse energy., Comment: 17 pages, 11 figures

We demonstrate a simple, robust, and contactless method for nondestructive testing of magnetic materials such as steel. This uses a fiber-coupled magnetic sensor based on nitrogen-vacancy centers (NVCs) in diamond without magnetic shielding. Previous NVC magnetometry has sought a homogeneous bias magnetic field on the diamond to improve the sensitivity. In contrast, here we show that the spatial resolution for imaging is improved by applying an inhomogeneous magnetic field to the steel even though this leads to an inhomogeneous magnetic field on the diamond. Structural damage in the steel distorts the inhomogeneous magnetic field and by detecting this distortion we reconstruct the damage profile through quantifying the shifts in the NVC Zeeman splitting. With a 1-mm magnet as the source of our inhomogeneous magnetic field, we achieve a high spatial resolution of 1 mm in the plane parallel and 0.1 mm in the direction perpendicular to the surface of the steel. This works even when the steel is covered by a nonmagnetic material. The lift-off distance of our sensor head from the surface of 316 stainless steel is up to 3 mm.

Nitrogen-vacancy centers (NVCs) in diamond are being explored for future quantum technologies, and in particular ensembles of NVC are the basis for sensitive magnetometers. We present a fiber-coupled NVC magnetometer with an unshielded sensitivity of $(310\ifmmode\pm\else\textpm\fi{}20)\phantom{\rule{0.2em}{0ex}}\mathrm{pT}/\sqrt{\mathrm{Hz}}$ in the frequency range of 10--150 Hz at room temperature. This takes advantage of low-strain ${}^{12}\mathrm{C}$ diamond, lenses for fiber coupling and optimization of microwave modulation frequency, modulation amplitude, and power. Fiber coupling means the sensor can be conveniently brought within 2 mm of the object under study.

We present characterization of a lock-in amplifier based on a field programmable gate array capable of demodulation at up to 50 MHz. The system exhibits 90 nV/sqrt(Hz) of input noise at an optimum demodulation frequency of 500 kHz.The passband has a full-width half-maximum of 2.6 kHz for modulation frequencies above 100 kHz. Our code is opensource and operates on a commercially available platform.

Background and objective: Inaccurate measurements of body temperature following cardiopulmonary bypass may be associated with serious complications. The purpose of this study was to determine whether axillary and tympanic temperature measurements correlate with the urinary bladder temperature in the early postcardiac surgery period. Methods: Forty-nine adult patients who underwent cardiac surgery under cardiopulmonary bypass at our institution were prospectively studied. Urinary bladder, right axillary, right tympanic and left tympanic temperature measurements were simultaneously recorded at 0, 6, 12 and 18 h following cardiopulmonary bypass. Patients had one to four sets of recordings and a total of 629 temperature measurements were recorded. The mean difference (bias) between the bladder and each of the other methods and limits of agreement were calculated using Bland and Altman method. Results: The mean core body temperature recorded from the bladder on admission to the intensive care unit was 36.4 degrees C. After 6, 12 and 18 h the mean core body temperature was 37.4 degrees C (range: 35.2-39.0), 37.5 degrees C and 37.45 degrees C, respectively. The mean differences (bias) between the bladder temperature and the other three methods were: left tympanic, 0.65 degrees C (95% CI: -0.24 to 1.58); right tympanic, 0.57 degrees C (95% CI: -0.48 to 1.63) and right axillary, 0.55 degrees C (95% CI: -0.27 to 1.36). Conclusions: The axilla and tympanic membrane are unreliable sites for core body temperature measurement early after cardiopulmonary bypass in adult patients and clinical decisions should be based on more reliable methods.

To survey the in-hospital morbidity, mortality, length of stay in the intensive therapy unit (ITU) and hospital and quality of life in patients of Indo-Asian origin following coronary artery bypass (CABG) surgery, 345 consecutive patients (mean age 58 years; SD 8.9; range 32-88 years) undergoing primary, isolated CABG were studied. Non-elective CABG was undertaken in 41% of patients. The left anterior descending artery (LAD) was grafted in 89%, although in 30% of these the internal mammary artery (IMA) was not used. Following CABG, the hospital morbidity and mortality was within the expected range, although there was a trend towards higher in-hospital mortality in the Parsonnet low risk group of patients. The length of ITU and hospital stay was not prolonged. Using the SF-36 questionnaire in postoperative patients, low quality of life scores were obtained for six of the eight modalities tested including physical functioning, bodily pain and general health perception. The low quality of life scores and IMA usage in Indo-Asians needs to be addressed.

A prospective electrophysiological study of phrenic nerve was performed in 59 subjects undergoing open-heart surgery. The nerve was stimulated percutaneously at the neck and the diaphragmatic response was recorded with surface electrodes placed over the 8th intercostal space. The latency, amplitude, duration and area of the evoked response were measured before and after the operation. Post-operatively no response was elicited in 2 patients bilaterally, in 5 from the left and in 2 from the right. Comparison of the post-operative with the pre-operative group values in the remaining subjects showed that the amplitude and area of the left phrenic were lower in the post-operative study, indicating that some of the nerve fibres were not conducting. There were no statistically significant differences between pre and post-operative values of latency or duration on the left or any of the parameters on the right. Our findings suggest that the amplitude and area of the diaphragmatic response are more sensitive than latency in detecting phrenic nerve paresis associated with open-heart surgery.

Alterations in cerebral blood flow (CBF) occurring during cardiopulmonary bypass (CPB), which are thought to be responsible for increased morbidity, are probably related to changes in arterial carbon dioxide during acid-base management. In this study, 70 patients undergoing elective coronary artery bypass surgery (CABS) were randomised to one of two differing, but widely practised, cardiopulmonary bypass acid-base protocols; pH-stat and alpha-stat. Cerebral blood flow was measured during surgery using the xenon-133 isotope clearance technique. Cerebral oxygen metabolism was measured as the cerebral metabolic rate for oxygen (CMRO2) and matching of the cerebral blood flow to oxygen demand as the cerebral extraction ratio for oxygen (CERO2). Detailed neuropsychological tests were conducted in all patients before surgery and repeated at 6 weeks after surgery for assessment of changes in cognitive function. During hypothermic (28 degrees C) CPB, CBF was significantly greater (P < 0.001) in the pH-stat group (41 ml/100 g per min; 95% confidence intervals (CI), 39-43) than in the alpha-stat group (24 ml/100 g per min; 95% CI, 22-26). The cerebral extraction ratio for oxygen indicated a degree of mismatch of cerebral perfusion and demand during CPB in both pH-stat and alpha-stat groups (0.12; 95% CI, 0.11-0.14 and 0.25; 95% CI, 0.22-0.28, respectively). This mismatch was far more pronounced in the pH-stat group than in the alpha-stat group, indicating greater disruption in cerebral autoregulation in the former group.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral dysfunction following cardiopulmonary bypass may be aggravated by altered autoregulation of cerebral blood flow. We have used trans-cranial Doppler to measure middle cerebral artery blood flow velocity during cardiopulmonary bypass managed by either pH-stat or alpha-stat acid-base protocols. Fourteen patients were studied, 7 in each group. During bypass at 28 degrees C, patients underwent incremental alterations in mean arterial pressure from 20-90 mmHg, maintaining systemic perfusion flow at 1.75 L/min per m2. The cerebral extraction ratio of oxygen was measured to indicate matching of cerebral blood flow to demand. The pH-stat group showed a pressure passive cerebral circulation with significant (r = 0.999, P less than 0.05) increase in blood flow velocity with increasing arterial pressure. This also occurred in alpha-stat group during the pressure range of 20-50 mmHg (r = 0.951, P less than 0.05). During the pressure range of 50-90 mmHg in alpha-stat group the change in flow velocity (0.16 cm/sec per mmHg) was significantly (P less than 0.05) less than that in pH-stat group (0.58 cm/second per mmHg). The cerebral extraction ratio of oxygen was less depressed in the alpha-stat group than in the pH-stat group, indicating more appropriate matching of cerebral blood flow and tissue demand. These results suggest that, during alpha-stat managed cardiopulmonary bypass, cerebral blood flow velocity is less subject to wide pressure alteration than pH-stat.

Metastatic tumours are the commonest cardiac tumours being found in 1-3% of patients dying of cancer while primary tumours are unusual and have an incidence of 0.02-0.5%. The majority (80%) of all primary cardiac tumours are benign with myxomas accounting for 50%. Myxomas arising from the right atrium are uncommon. We present the case of a 39-year-old female with a 4-month history of progressive exertional dyspnoea accompanied by symptoms of palpitations and presyncope. Transthoracic echocardiography showed an extremely large right atrial myxoma prolapsing into the right ventricle and obstructing the tricuspid valve. We demonstrate how intraoperative transoesophageal echocardiography, prior to sternotomy, was useful in providing information about the myxoma which clearly displayed its attachment and anatomical relationship in the planning of the 'safe' surgical excision.

Arterial catheters are routinely used to sample blood for clotting studies in most cardiothoracic intensive care units. The clotting profile in surgical bleeding after cardiac surgery influences further management. Aspiration and discard of a certain amount of blood from the line, prior to sampling, are assumed to clear heparin contamination. We have investigated this assumption through analysis of the clotting profile by simultaneous arterial line and peripheral venous samples.The morning following cardiac surgery, simultaneous arterial line and peripheral venous blood samples were taken for activated plasma thromboplastin time (APTT) ratio and international normalized ratio (INR) in 49 randomly selected patients. Also, a thromboelastogram analysis (TEG) (n = 7) was made. A survey of 22 UK cardiothoracic intensive care units was carried out to determine the practice for the withdrawal of blood for clotting studies.The median arterial APTT ratio value was 1.32 +/- 0.52 as compared to the median peripheral APTT ratio value which was 1.1 +/- 0.24 (P0.001). INR values were statistically similar by both routes. Heparin contamination was confirmed by TEG which revealed that the R-value for arterial catheter blood samples without heparinase in the cup was higher (406.00 +/- 64.44 s) compared with the value for arterial samples with heparinase in the cup (318.28 +/- 47.26s, P0.05). The survey of 22 UK cardiothoracic intensive care units showed that heparinized arterial lines were by far the commonest ports used for blood withdrawal for the measurement of APTT ratio results.Samples withdrawn from heparinized arterial lines cannot be relied upon for APTT ratio results.

After aortic valve replacement (AVR), 90% of survivors are in NYHA class I or II, and most return to work after three months. It is unclear, however, whether at that time patients have an improved quality of life (QOL), are able to perform physical and social activities, and live independently.To assess this situation, 62 patients (39 males, 23 females; mean age 68.5 +/- 10 years) who underwent primary AVR completed the validated Short Form 36 (SF-36) questionnaire. QOL parameters were determined before and three months after surgery prospectively, and analyzed using the Wilcoxon matched pairs rank test.All patients showed significant improvement in all eight QOL parameters (score 0-100): (i) physical function (67 +/- 26 versus 37 +/- 28; p0.00001); (ii) role limitation due to physical function (52 +/- 43 versus 20 +/- 37; p0.0001); (iii) social function (80 +/- 25 versus 59 +/- 30; p0.0001); (iv) role limitation due to emotional problems (64 +/- 41 versus 41 +/- 46; p = 0.01); (v) energy (62 +/- 22 versus 42 +/- 23; p0.00001); (vi) mental health (78 +/- 19 versus 63 +/- 22; p0.00001); (vii) pain (78 +/- 27 versus 67 +/- 32; p = 0.02); and (viii) general health perception (72 +/- 20 versus 58 +/- 21; p0.00001). Significant improvements in QOL parameters were: (i) after mechanical and bioprosthetic AVR, seven of eight QOL parameters were improved; (ii) patients aged70 years had pronounced improvement in six of seven parameters, while those agedor = 70 years had limited improvement in five of eight parameters; (iii) patients with valve sizes 19 and 21 mm improved in five of eight parameters, while those withor = 23 mm implants improved in all eight parameters, regardless of post-AVR peak gradient of20 oror = 20 mmHg; and (iv) patients with left ventricular end-diastolic dimension (LVEDD)55 mm improved in all eight parameters while those with LVEDDor = 55 mm improved in only five parameters.There was significant improvement in patients' QOL at three months after AVR, regardless of the type of aortic implant used; improvement was greatest in those aged70 years. The results also suggest that patients with smaller implants (who were older) and those with LVEDDor = 55 mm were less likely to show significant improvement in all QOL parameters at three months after AVR.

The surgeon's bare fingertips and the external surface of gloved fingertips were examined for contamination by bacteria during the course of 27 cardiac surgical operations. Following the surgical scrub, positive colony counts were obtained in 20 (74%) of bare fingertip impressions (median colony count 4 [inter-quartile range, IQR, 0-9)], while at the conclusion of surgery positive counts were obtained in 15 (55.6%) fingertip impressions (median count 1 [IQR 0-6]; range 0-247; paired Wilcoxon test p = NS). Furthermore, positive colony counts at the start of the operation were obtained in none of the gloved fingertip impressions and at conclusion of surgery in 17 (62.9%) of the gloved fingertip impressions (median count 2 [IQR 0-6] p = 0.0002). There was no significant relationship between the total colony count on gloved fingertip impressions and the length of surgery (Pearson's r = 0.17, p = NS). Contrary to expectations there was no significant increase in the colony count on the bare fingertips at the conclusion of surgery. Although there was an increase in the bacterial count on the surgeon's gloved fingertips, this increase did not correlate with the length of surgery.

An increasing number of elderly patients are now requiring mitral valve surgery (MVS). However, due to a perceived increase in risk of morbidity and mortality following cardiac surgery, many elderly patients tend to be neglected or not referred for surgery.The outcome of MVS in terms of hospital morbidity and mortality, length of intensive care unit (ICU) and hospital stays, and change in NYHA functional class and quality of life following surgery was assessed in 43 elderly patients (18 males, 25 females; median age 77 years (IQR 75-82 years)) who underwent primary open mitral valve repair (MVRr) or replacement (MVR) between November 1994 and September 1997. Their preoperative clinical characteristics, incidence of hospital morbidity, hospital mortality and length of ICU and hospital stays following MVS were recorded. At follow up, NYHA class was assessed and quality of life parameters monitored using the SF-36 questionnaire.At surgery, 69% of patients were in NYHA class III/IV, 36% underwent non-elective surgery and 44% had symptoms of more than three years' duration. Among patients, 80% presented with mitral incompetence and MVRr was undertaken in 51%. The median bypass and cross-clamp times for MVRr were significantly longer than for MVR. After surgery, 98% of patients required inotropic support, 9% renal dialysis, and 42% ventilatory support for24 h. In addition, 37% developed respiratory complications, 12% renal failure, 19% needed re-exploration for bleeding, and 5% suffered a stroke. The mean ICU stay after surgery was three days; average in-hospital stay was 10 days. The 30-day mortality rate was 22.7% after MVRr and 38% after MVR. There was a significant improvement in energy, and role limitation due to physical and mental health after MVS.Elderly patients underwent MVS, usually after a degree of clinical deterioration. Although morbidity and mortality following mitral valve surgery were high, at follow up there was a significant improvement in both symptoms and quality of life of survivors.

Neuropsychologic impairment in patients undergoing cardiopulmonary bypass may be associated with cerebral blood flow changes arising from different management protocols for carbon dioxide tension during bypass. Seventy patients having coronary artery bypass grafting were randomized to either pH-stat or alpha-stat acid-base management during cardiopulmonary bypass with a membrane oxygenator. In each patient, cerebral blood flow (xenon 133 clearance), middle cerebral artery blood flow velocity (transcranial Doppler sonography), and cerebral oxygen metabolism (cerebral metabolic rate and cerebral extraction ratio) were measured during four phases of the operation: before bypass, during bypass (at hypothermia and at normothermia), and after bypass. A battery of neuropsychologic tests were also conducted before and 6 weeks after the operation. During hypothermic (28º C) bypass, cerebral blood flow was significantly (p < 0.001) greater in the pH-stat group (41 ml•100 gm -1 •min -1 ; 95% confidence interval 39 to 43 ml•100 gm -1 •min -1 ) than in the alpha-stat group (24 ml•100 gm -1 •min -1 ; confidence interval 22 to 26 ml•100 gm -1 •min -1 ) at constant pressure and flow. Arterial carbon dioxide tensions were 41 mm Hg (40 to 41 mm Hg) and 26 mm Hg (25 to 27 mm Hg), respectively; pH was 7.36 (7.34 to 7.38) and 7.53 (7.51 to 7.55), respectively. Middle cerebral artery flow velocity was significantly (p < 0.05) reduced in the alpha-stat group to 87% (77% to 96%) of the prebypass value, whereas it was significantly (p < 0.05) increased (152%; 141% to 162%) in the pH-stat group. Cerebral extraction ratio for oxygen demonstrated relative cerebral hyperemia during hypothermic (28º C) bypass in both the pH-stat and alpha-stat groups (0.12 [0.11 to 0.14] and 0.25 [0.22 to 0.28], respectively); however, hyperemia was significantly more pronounced in the pH-stat group, indicating greater disruption in cerebral autoregulation. Neuropsychologic impairment criteria of deterioration in results of three or more tests revealed that a significantly (Fisher's exact test, p = 0.02) higher proportion of patients in the pH-stat group fared poorly than in the alpha-stat group at 6 weeks (17/35, 48.6% [32% to 65.1%], and 7/35, 20% [6.7% to 33.2.2%], respectively). In conclusion, patients receiving alpha-stat management had less disruption of cerebral autoregulation during cardiopulmonary bypass, accompanied by a reduced incidence of postoperative cerebral dysfunction. (J THORAC CARDIOVASC SURG 1996;111:1267-79)

Alterations in cerebral blood flow (CBF) occurring during cardiopulmonary bypass (CPB), which are thought to be responsible for increased morbidity, are probably related to changes in arterial carbon dioxide during acid-base management. In this study, 70 patients undergoing elective coronary artery bypass surgery (CABS) were randomised to one of two differing, but widely practised, cardiopulmonary bypass acid-base protocols; pH-stat and alpha-stat. Cerebral blood flow was measured during surgery using the xenon-133 isotope clearance technique. Cerebral oxygen metabolism was measured as the cerebral metabolic rate for oxygen (CMRO2) and matching of the cerebral blood flow to oxygen demand as the cerebral extraction ratio for oxygen (CERO2). Detailed neuropsychological tests were conducted in all patients before surgery and repeated at 6 weeks after surgery for assessment of changes in cognitive function. During hypothermic (28 degrees C) CPB, CBF was significantly greater (P0.001) in the pH-stat group (41 ml/100 g per min; 95% confidence intervals (CI), 39-43) than in the alpha-stat group (24 ml/100 g per min; 95% CI, 22-26). The cerebral extraction ratio for oxygen indicated a degree of mismatch of cerebral perfusion and demand during CPB in both pH-stat and alpha-stat groups (0.12; 95% CI, 0.11-0.14 and 0.25; 95% CI, 0.22-0.28, respectively). This mismatch was far more pronounced in the pH-stat group than in the alpha-stat group, indicating greater disruption in cerebral autoregulation in the former group.(ABSTRACT TRUNCATED AT 250 WORDS)

Haemodynamic studies have shown that diseased cardiac valves, whether stenosed or incompetent, create regions of increased turbulence and shear stresses that are large enough to damage the vascular endothelium and cellular blood elements, leading to abnormal haemorheology, platelet activation, and endothelial dysfunction.1 For example, the intensity of turbulence in patients with pure aortic stenosis (AS) may be 10 times greater than normal while the intensity of turbulence in patients with pure aortic regurgitation (AR) may be three times greater than normal1. We hypothesised that patients with aortic valve disease may show abnormal haemorheology, platelet activation, and endothelial dysfunction, that may increase their risk of thromboembolism. These abnormalities may perhaps reflect haemodynamic changes resulting from AS or AR, in particular their respective severity. To test our hypothesis, we measured plasma concentrations of soluble P-selectin (sP-sel, a marker for platelet activation2), von Willebrand factor (vWf, a marker for endothelial cell dysfunction3) and fibrinogen (as an index of haemorheology and a clotting factor), in 61 patients with moderate to severe aortic valve disease in sinus rhythm. We recruited consecutive patients attending outpatient clinics or admitted to our regional referral cardiothoracic unit with primary (native) aortic valve disease. We excluded patients with atrial fibrillation, patients on warfarin, statins or hormone replacement therapy, those with double valve disease (namely, mitral and aortic valve disease) and associated medical conditions known to influence the markers under investigation (including coronary artery …

(±)-4-Methoxybenzoin has been resolved by fractional crystallisation of the quinidine salt of its hydrogen phthalate ester.

(±)-4-Dimethylaminobenzoin has been resolved by fractional crystallisation of the quinidine salt of its hydrogen phthalate.