1,878 research outputs found
Agricultural Growth in China and Sub-Saharan African Countries
Agriculture remains a dominant sector in the economies of most African and several Asian countries. However, the poor performance of agriculture in Africa stands in sharp contrast to the robust agricultural growth in many Asian countries.2 In this regard, the experience of China is perhaps as impressive as it is relevant to many countries in Sub-Saharan Africa. A general observation is that the productivity of land and labour has to rise through intensive agriculture, given the limited area of arable land (in China and Africa) and the high rates of growth of population (as in Africa). In many African countries, labour productivity has fallen and land productivity has not increased significantly. In China, productivities of both land and labour have increased significantly since at least the early 1980s. Agricultural output can increase in three ways: (i) get more from the same quantities of inputs through better utilisation of the existing capacity; (ii) use increased quantities of inputs; and (iii) use new techniques to raise the productivity of each input or raise the total product curve. All of these may require changes in tenurial arrangements, levels of investment in infrastructure and support services, and policies that affect the prices of outputs and inputs. A close examination of factors underlying the contrasting experiences in China and African countries reveals important differences in the institutional and policy environments affecting the individual behaviour with regard to the adoption and use of new (profitable) technologies to raise the land and labour productivities.
A Quantum Key Distribution Network Through Single Mode Optical Fiber
Quantum key distribution (QKD) has been developed within the last decade that
is provably secure against arbitrary computing power, and even against quantum
computer attacks. Now there is a strong need of research to exploit this
technology in the existing communication networks. In this paper we have
presented various experimental results pertaining to QKD like Raw key rate and
Quantum bit error rate (QBER). We found these results over 25 km single mode
optical fiber. The experimental setup implemented the enhanced version of BB84
QKD protocol. Based upon the results obtained, we have presented a network
design which can be implemented for the realization of large scale QKD
networks. Furthermore, several new ideas are presented and discussed to
integrate the QKD technique in the classical communication networks.Comment: This paper has been submitted to the 2006 International Symposium on
Collaborative Technologies and Systems (CTS 2006)May 14-17, 2006, Las Vegas,
Nevada, US
Relative Efficiency by Farm Size and the Green Revolution in Pakistan
Using the "unit output price" profit function, the study
analyses the relative efficiency of (a) old versus new seeds, and (b)
large versus small farms in the production of new varieties of wheat and
rice in the Indus Basin of Pakistan. It is found that whereas farm .size
has no effect on efficiency, high-yielding seeds are more efficient than
seeds of old varieties. The study also finds that labour demand
elasticities with respect to both land and capital are rather
low
Exploring cucumber extract for skin rejuvenation
This study was designed to develop a topical skin-care cream water in oil (w/o) emulsion of 3% cucumber extracts versus its vehicle (Base) as control and evaluates its effects on skin-melanin, skin erythema, skin moisture, skin sebum and transepidermal water loss (TEWL). Hydroalcohol.c cucumber (Cucumis sativus) fruit extract was entrapped in the inner aqueous phase of w/o emulsion. Base containing no extract and a formulation containing 3% concentrated extract of C. sativus was formulated. The odour was adjusted with few drops of lemon oil. Both the base and formulation were stored at different storage conditions for a period of 4 weeks to predict their stability. Different stability parameters that is: Physical stability, centrifugation and pH were monitored at different time intervals. Both the base and formulation were applied to the cheeks of 21 healthy human volunteers for a period of 4 weeks. The expected pharmaceutical stability of creams was achieved from 4 weeks in vitro study period. Odour disappeared with passage of time due to volatilization of lemon oil. The base showed insignificant (p > 0.05) effects on all skin parameters except sebum that was not significant, whereas the formulation showed statistically significant (p.0.05) effects on skin sebum secretion. TEWL and erythema was increased while skin melanin and skin hydration level was decreased by formulation. However these effects were statistically insignificant (p > 0.05). The results showed a good stability over 4 weeks of observation period of both base and formulation and the formulation has anti sebum secretion, bleaching and moisturizing effects.Key words: Cucumber extract, melanin, skin moisture, skin sebum, transepidermal water loss (TEWL)
Phytochemical analysis and bioactivity screening of three medicinal plants of Saudi Arabia
Purpose: To investigate the phytochemical analysis and bioactivity screening of some Asteraceae medicinal plants.
Methods: The chemical constituents were isolated by column chromatography and elucidated using chemical and extensive spectroscopic methodologies including gas chromatoraphy-mass spectrometry (GC-MS), Fourier transform infrared spectroscopy (FTIR), as well as 1D and 2D nuclear magnetic resonance (NMR). The plant extracts were obtained by solvent extraction method while hydrodistillation was used to isolate plant essential oils. Furthermore, cup-plate agar diffusion was applied for antimicrobial activity evaluation while minimum inhibitory concentration (MIC) was assessed by microdilution technique.
Results: Centaurea pseudosinaica, Tripleurospermum auriculatum, and Koelpinia linearis afforded previously undescribed three coumarins (xanthotoxin, cirsimaritin, salvigenins) from C. pseudosinaica, one steroid (estradiol) and a pentacyclic triterpene (β-amyrin) from T. auriculatum and a coumarin (santin) from K. linearis in good yields. In addition, the plant extracts and oils exhibited remarkable bioactivities including antifungal, antibacterial and antipyretic etc.
Conclusion: The results reveal the presence of bioactive phytomolecules from Asteraceae plant extracts and volatile oils from three Asteraceae plants.
Keywords: C. pseudosinaica, T. auriculatum, K. linearis, Xanthotoxin, Salvigenin, Cirsimaritin, Santin, Estradiol, β-amyrin, Antimicrobial activit
Surgical Management of Soft Tissue Sarcoma
Background: To study the management patternof soft tissue sarcomas in a tertiary care settingMethods: In this descriptive study patients whowere operated for soft tissue masses were included.Intra-operative findings, procedure details andpostoperative orders were recorded. Postoperativechemo-radiotherapy records were reviewed andrecorded. Depth of the tumour was grouped asdeeper or superficial than 5 cm. The follow uprecords were accessed from the outpatientdepartment and any surgical complications wererecorded up to three years.Staging was done usingclinical and radiological criteria taking into accountthe histological grade,tumour size , depth, locallymph node invasion and metastasis.Surgicalprocedure for removal of STS are wide local excision(WLE), intralesional excision (IE) or tumordebulking, marginal excision (ME) and radicalexcision (RE).Results: Sixty eight patients with mean age of 43.0± 17.258 SD were diagnosed as cases of soft tissuesarcomas. Male to female ratio was 3.25:1.The mostcommon histopathological variety was malignantfibrous histiocytoma (35.3%) , followed byRhabdomyosarcoma(30%). Most common involvedsite was lower limbs (35.3%).Wide local excision wasperformed in majority (82.4%) . Most commonpostop complication was wound infection (10.3%)Conclusion: Clinicians must be agile about thenature of these tumours and their referral to aspecialist surgeon for further management. Promptdiagnosis, accurate investigations and earlyintervention will benefit the patients and help usunderstand this disease entity
Correlation of troponin-I level with left ventricular systolic dysfunction after first attack of non-ST segment elevation myocardial infarction
Background: Coronary Heart Disease (CHD) is the most common category of the heart disease and is found to be the single most important cause that leads to premature death in the developed world. Recognizing a patient with ACS is important because the diagnosis triggers both triage and management. cTnI is 100% tissue-specific for the myocardium and it has shown itself as a very sensitive and specific marker for AMI. Ventricular function is the best predictor of death after an ACS. It serves as a marker of myocardial damage and provides information on systolic function as well as diagnosis and prognosis. The study aimed at investigating the impact of LVEF on elevated troponin-I level in patients with first attack of NSTEMI.Methods: This cross-sectional analytical study was conducted in the department of cardiology in Mymensingh Medical College Hospital from December, 2015 to November, 2016. Total 130 first attack of NSTEMI patients were included considering inclusion and exclusion criteria. The sample population was divided into two groups: Group-I: Patients with first attack of NSTEMI with LVEF: ≥55%. Group-II: Patients with first attack of NSTEMI with LVEF: <55%. Then LVEF and troponin-I levels were correlated using Pearson’s correlation coefficient test.Results: In this study mean troponin-I of group-I and group-II were 5.53±7.43 and 16.46±15.79ng/ml respectively. It was statistically significant (p<0.05). The mean LVEF value of groups were 65.31±10.30% and 40.17±4.62% respectively. It was statistically significant (p<0.05). The echocardiography showed that patients with high troponin-I level had low LVEF and patients with low troponin-I level had preserved LVEF. Analysis showed that patients with highest level of troponin-I had severe left ventricular systolic dysfunction (LVEF <35%) and vice versa-the patients with the lowest levels of troponin-I had preserved systolic function (LVEF ≥55%). In our study, it also showed that the levels of troponin-I had negative correlation with LVEF levels with medium strength of association (r= -0.5394, p=0.001). Our study also discovered that Troponin-I level ≥6.6ng/ml is a very sensitive and specific marker for LV systolic dysfunction.Conclusions: The study has enabled the research team to conclude that the higher is the Troponin-I level the lower is the LVEF level and thus more severe is the LV systolic dysfunction in first attack of NSTEMI patients
An energy efficient interference-aware routing protocol for underwater WSNs
Interference-aware routing protocol design for underwater wireless sensor networks (UWSNs) is one of the key strategies in reducing packet loss in the highly hostile underwater environment. The reduced interference causes efficient utilization of the limited battery power of the sensor nodes that, in consequence, prolongs the entire network lifetime. In this paper, we propose an energy-efficient interference-aware routing (EEIAR) protocol for UWSNs. A sender node selects the best relay node in its neighborhood with the lowest depth and the least number of neighbors. Combination of the two routing metrics ensures that data packets are forwarded along the least interference paths to reach the final destination. The proposed work is unique in that it does not require the full dimensional localization information of sensor nodes and the network total depth is segmented to identify source, relay and neighbor nodes. Simulation results reveal better performance of the scheme than the counterparts DBR and EEDBR techniques in terms of energy efficiency, packet delivery ratio and end-to-end delay
Delayed presentation of forgotten thyroid goiter - 25 years after thyroidectomy
Forgotten goiter is a rare occurrence (2 - 16% of retrosternal thyroid cases) that depicts recurrence of retrosternal thyroid mass due to growth of remnant thyroid tissue overlooked during an initial thyroidectomy. The patient is a 59-year female who presented with dyspnea and stridor 25 years after total thyroidectomy. She was diagnosed as having a mediastinal mass on radiographic imaging. There were only localized pressure symptoms due to mass effect. The mass was excised employing an extra-cervical approach and using a partial sternotomy. The profuse extension of thyroid tissue, adherent to vital structures in the thorax and the extra-cervical thyroidectomy was a novel experience. The mass was completely excised and the patient\u27s symptoms alleviated after the surgery. The patient recovered without any complications and there was no recurrence at 1 year of follow-up
Determinants of Increasing Trend of Self-Medication in a Pakistani Community
Purpose: To determine the major reasons, sources, diseases and drugs responsible for increasing trend of self-medication.Method: A community-based cross-sectional survey was carried out in the district of Faisalabad in Pakistan. Respondents (1488) were classified on the basis of age, sex, education, lifestyle and their economical level. A questionnaire was distributed among the sample population to collect data.Results: Majority of respondents involved in self-medication were aged between 15 and 20 years. Family members (N = 717, 48 %) were considered the major source of information for self-medicated drugs. Lack of time (N = 504, 37 %) while economic issues (N = 485, 33 %) were the major reasons for self-medication. Medical stores were the source of drug purchase by 1087 (73 %) respondents. Headache (N = 772, 52 %) and fever (N = 600, 40 %) were the main indications for self-medication while 694 respondents reported that they engage in single-dose self-medication. Paracetamol (N = 689, 46 %), other analgesics (N = 488, 33 %), non-steroidal anti-inflammatory (N = 680, 46 %) were reported to be used frequently for self-medication.Conclusion: Self-medication is prevalent in the Pakistani community due to easy access to over the counter (OTC) and prescription-only medicines (POM). This may lead to untoward effects in consumers of the products. Special interventions by relevant regulatory agencies regarding the sale of the drugs are therefore required.Keywords: Self-medication, OTC drugs, Pharmacist
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