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Purpose: Destructive eye surgeries have been described as necessary evils. Even though they are important and sometimes life-saving, their psychological impacts on the patients are many. This study sought to determine the prevalence and main indications of evisceration in Our Lady of Grace Hospital in the Asikuma–Odoben-Brakwa District of the Central Region of Ghana. Methodology: The mixed method study design was used. A five-year review of all cases of eviscerations from 2012-1016, was conducted. Also, in-depth interviews of 9 patients purposively selected, who had undergone eviscerations during the period under review were conducted. Data analysis was largely descriptive. Result: Out of a total of 2996 ocular surgeries conducted within the 5-year period, 101 were eviscerations. This gives a 5-year prevalence of 3.4 per 100 surgeries. Out of the 101 cases of eviscerations, 81 were included in the analysis due to the availability of complete data. The mean age of patients was 50 years (SD 1.53). The majority of patients who underwent eviscerations were 60 years and more. Right (51%) and left (49%) eyes were eviscerated in nearly equal proportion. The occupations of the majority of patients were farmers/fisherfolks (55.6%) and trading (19.8%). Most (76.5%) eviscerations were due to non-trauma-related causes mainly infections (55.6%). The trauma-related indications for evisceration (23.4%) were stick/vegetative materials, stone/particles, and assault. Unique Contribution to Theory, Policy and Practice: Eye infections and injuries which are largely preventable were the main causes of eviscerations in this study. Public education to encourage early reporting is needed. The aged should be discouraged from engaging in unprotected manual farm-related activities.

PURPOSE The purpose of this study was to investigate the utility of two ocular biometric measurements to obtain Hirschberg ratios (HRs) in a binocularly normal paediatric population, and to assess the repeatability of this approach. METHODS Ocular biometry data from 80 participants (aged 5 to 14 years) was obtained using the KM-1 LED manual keratometer and the Tomey Biometer AL-100 A-scan. HRs were calculated from corneal curvature and anterior chamber depth measurements in the horizontal and vertical meridians of each eye using a regression equation based on a geometric optics model. To assess intrasubject variability in the HRs obtained from biometry, measurements were repeated approximately 1 h later. RESULTS At the initial measurement, mean (SD, range) HRs were 10.77 (0.79, 9.14-12.73) and 11.02 (0.82, 9.48-13.32) °/mm for the horizontal and vertical meridians, respectively. There was a significant difference between the horizontal and vertical HRs (p

Background: Reduced visual function is associated with diminished quality of life as well as decreased physical and mental health. Poor visual function related to cataracts is also a risk factor for falls and traffic accidents, which may lead to hospital admissions and limit independence. Objective: To evaluate patients’ satisfaction, visual functions and spectacle independence among patients in the Central Region of Ghana who had cataract surgery in one eye. Methods: A hospital-based prospective cohort study was carried out on 146 patients booked for cataract surgery: 16 were lost through follow-ups whilst 130 completed the study. Visual functions including visual acuity, contrast sen- sitivity, stereopsis and colour vision were assessed before and after a month of cataract surgery. Objective and subjective refractions were performed to determine the post-surgery refractive status of the participants. Participants completed the NEI-VFQ 25 questionnaire and the scores obtained were used as a construct of their satisfaction. Results: The NEI-VFQ 25 questionnaire scores indicated patients’ satisfaction was high with an average quality of life score of 77.46. Patients satisfaction was strongly correlated with contrast sensitivity (r=0.653, p0.001) association between spectacle independence and the two types of cataract surgery performed which included Small Incision Cataract Surgery (SICS) and Extracapsular Cataract Extraction (ECCE). Among those who were spectacle independent, 53.4% of them were low vision patients. Conclusion: Satisfaction of patients after cataract surgery was high but was greatly influenced by visual functions with contrast sensitivity being a better predictor of satisfaction than visual acuity and stereopsis. Spectacle independence after cataract surgery was low at distance and extremely low at near. The type of cataract surgery performed influenced thespec- tacle independence. Keywords: TNO; contrast sensitivity; spectacle independence; cataract surgery; intraocular lens.

Field experiment was conducted to investigate the response of soil physical properties, crop growth, yield and yield components of watermelon to different tillage methods in the transitional zone of Ghana in a two year period. The tillage treatments used in the study were plough and harrowed (PH), minimum tillage (MT) and no tillage (NT) which was laid out in a Randomized Complete Block design (RCBD) with 3 three replications. The two field experiments were undertaken at the experimental site of the University of Education, College of Agriculture, Mampong-Ashanti, (7°08‘ N, 1°24‘ W )located within the transitional agro-ecological zone between the forest and Guinea Savannah zones characterized with two rainfall regimes with an annual rainfall of 1094.2 mm with 30°C temperature. The soil belongs to the Bediase series with ochrosol type formed from voltain sandstone and a pH between 5.5 to 6. The statistical analysis revealed that, tillage methods significantly affected soil physical properties particularly, total porosity, volumetric water content and bulk density. Also, tillage methods influenced crop growth, (number of leaves and vine length), yield and yield components of watermelon in the order of Plough and harrowed > Minimum tillage > No-Tillage in almost all the treatments. Accordingly, the ploughed and harrowed (PH) was found to be more appropriate and profitable tillage method to improving soil physical properties, crop growth, yield and yield components of watermelon in the forest-transitional of Ghana.

Crops, soil and fish from irrigation farms were investigated in the Upper East Region of Ghana. Questionnaire was administered to collect pesticide use information from farmers, and tomatoes, okro, pepper and garden eggs as well as fish and soil samples were collected and analysed using Gas Chromatography-Electron Capture Detector (GC-ECD). The results were compared with standard acceptable Maximum Residue Limits (MRLs). The results indicated that up to 35.9% of 50 respondent farmers frequently cultivated tomatoes. 50% of the farmers have been using agrochemicals for the past 5 years, with glyphosphate as the most commonly used (42%). 65 % of the farmers indicated that information on proper use or handling of agrochemicals was obtained from colleague farmers. High levels of organochlorine residues (2.232-5.112 ng/g) were found in okro and garden eggs from the Tono site, and also pepper and tomatoes from Pungu site. 6 pesticides residues were found in 5 varieties of tomatoes samples analysed with Lindane and Aldrin having the highest concentration of 0.00069 and 0.027 μg/g respectively. 4 soil samples contained detectable levels of β-HCH and α-Endosulfan (organochlorines), while all 6 samples had one or more traces of 10 organophosphate pesticides. Chlorpyrifos was widely available and in quite high levels. 21 organochlorine residues were detected in tilapia and mud fishes, 17 in fishes from the Precast yard water. Residual concentration of Aldrin and Cis-heptachlor (1069.7 ng/g and 780.7 ng/g respectively) in tilapia from the Tono dam was noted to be above the acceptable limits.

The structural use of concrete depends largely on its strength, especially compressive strength.Various tests were carried out to ascertain the properties of concrete materials, whereas test performances ofthe concrete with different mix ratios at specific ages of curing were undertaken. The study determined thecompressive strength of concrete using different curing methods. Four different methods of curing (ponding,continuous wetting, open-air curing and sprinkling with water) were used. Seventy-two (72) cubes were castusing a mix ratio of 1:2:4 and 1:3:6 with 0.5 water cement ratio and with 0.6 waters cement ratio respectively.The compressive strengths were determined after 7 days, 14 days and at 28 days of curing. Findings showthat for 1:2:4 concrete, maximum of 28-day compressive was the highest for concrete cured by ponding andthe least was by sprinkling water. Further findings show that for 1:3:6 concrete, maximum of 28-daycompressive strength was obtained using ponding and the least was open air curing. Despite ponding methodproducing the highest compressive strength of concrete, it is practically impossible to cure cubes aboveground structural elements. Wet-covering method is recommended for structural elements, such as columns,beams and slabs in other to produce concreteof a required compressive strength.

Ghana’s Western North and Central Regions are biodiversity-rich landscapes. Cocoa is a major commodity produced in these two regions, accounting for over 50% of Ghana’s cocoa output. As part of the efforts to further improve productivity and ecological health of the landscape, the Government of Ghana initiated the Cocoa Disease and Pests Control Programme primarily to control cocoa pests and diseases, including the use of pesticides. In recent times, however, there has been an upsurge in the use of highly hazardous pesticides (HHPs) that have far-reaching consequences on human and ecological health of the cocoa production landscape. To gain a better understanding of pesticide-use patterns on cocoa farms and address HHP-driven biodiversity loss, Conservation Alliance International (CA) conducted a study within the landscape. The study was based on both qualitative and quantitative research approaches to understand pesticide use and resulting impacts on human and ecological health. In all, 306 cocoa farmers were surveyed. Analysis of the data revealed that about 81% of the cocoa farmers use pesticides to address pests and diseases, causing visible impacts on humans and the environment, including skin irritation, eye irritation, and death of pollinators. Pesticide use was exacerbated by the adverse economic impacts of the COVID-19 pandemic. Policymakers are therefore advised to take steps to phase out HHPs, promote integrated pest management, and tackle the spread of COVID-19 infections.

Rhesus macaques are a common non-human primate model used in the evaluation of human monoclonal antibodies, molecules whose effector functions depend on a conserved N-linked glycan in the Fc region. This carbohydrate is a target of glycoengineering efforts aimed at altering antibody effector function by modulating the affinity of Fcγ receptors. For example, a reduction in the overall core fucose content is one such strategy that can increase antibody-mediated cellular cytotoxicity by increasing Fc-FcγRIIIa affinity. While the position of the Fc glycan is conserved in macaques, differences in the frequency of glycoforms and the use of an alternate monosaccharide in sialylated glycan species add a degree of uncertainty to the testing of glycoengineered human antibodies in rhesus macaques. Using a panel of 16 human IgG1 glycovariants, we measured the affinities of macaque FcγRs for differing glycoforms via surface plasmon resonance. Our results suggest that macaques are a tractable species in which to test the effects of antibody glycoengineering.

The use of inorganic fertilizer to produce most vegetables in Ghana like carrot is in ascendency in Asante Mampong and its environs and its continuous use has a rippling effect on soil health and productivity and the high cost of these fertilizers is a challenge to most poor resourced farmers in Ghana. A field experiment was conducted during the major raining season in 2010 at the University of Education Winneba, Faculty of Agriculture Education research field at Mampong in the forest-transitional zone of Ghana on the Bediase series. The objective of the study was to evaluate the effect of grasscutter manure in combination with NPK fertilizer on soil physical and chemical properties, growth and yield of carrot. The treatments were 300 kgNPK/ha, combination of half rate NPK fertilizer and different rates of grasscutter manure (GM) thus; (5tGM1/ha+150 kgNPK, 7.5tGM2/ha+150 kgNPK and 10tGM3/ha+150 kgNPK/ha) and control (without amendment) and the experiment was laid out in a randomized complete block design with 3 replications. Results indicates that application of grasscutter manure in combination with NPK fertilizer significantly improved the soil physical conditions particularly, soil bulk density, total porosity, and gravimetric moisture content than the NPK alone and the control. Compared with the control, the treatment combinations significantly increased soil organic carbon, N, organic matter concentrations and exchangeable cations. Plant height, number of leaves, tap root length and root yield of treatment combinations were higher than NPK and the control. Also the treatment combinations significantly reduced nematode presence and number of roots deformed. For good soil health, grasscutter manure in combination with NPK would be better than either manure or NPK alone.

Purpose Users of smallholder farmer microfinance are able to make enough returns to repay credits advanced to them. However, they are in dire need of financial capital such that they are inconsiderate of farmer- and credit-specific characteristics when participating in a microfinance programme. This study analyses perceptions of stakeholders regarding select farmer and credit characteristics within the microfinance industry. The study identifies and analyses the factors that influence participation in a microfinance programme by farmers using the logistic regression model. The purpose of this paper is to widen the knowledge base of rural agricultural finance, including factors that influence participation in microfinance intervention(s) thereof. Design/methodology/approach A total of 104 participants and 120 non-participant farmers in microfinance programmes were interviewed using a semi-structured questionnaire by applying the multistage sampling technique. The paper applied the logistic regression model in which farmer- and credit-specific characteristics were used to estimate the probabilities of participation. Findings The logistic regression results showed that distance, interest rate, experience, membership of farmer-based organisation, number of dependants, household, gender and age were statistically significant farmer- and credit-specific characteristics that influence participation in microfinance programmes. Interest rate and distance exact negative significance influence on participation, whereas membership of farmer-based organisations, experience, gender, household head and age influence participation positively. Reduction in the interest rate and expansion of microfinance to very remote areas rather than locations in urban areas are crucial in terms of improving participation. Research limitations/implications The paper used data from only farmers so there is a limit to which the results can be generalised for all microfinance users. It may be relevant to undertake a study that considers non-farm enterprises. Practical implications This paper brings to light the need to develop well-structured microfinance facilities that meet the specific needs of the rural poor in transitioning economies while taking into consideration critical factors affecting participation before the establishment of such programmes. Originality/value This paper provides empirical evidence to show that farmer- and credit-specific characteristics are essential to ensure participation and success of microfinance programmes thereof.

Since titles are gateways to the heart of research articles (RAs), their organisational structure should be regarded very crucial in appealing to the potential reader. This study aimed to investigate how titles of RAs are presented in three disciplines (Gynaecology/Obstetrics, Business, and Law). After a thorough study of 574 titles, the study revealed that Business titles were averagely longer than those in the other two disciplines. In terms of title style, it was revealed that the Single Unit Title was extensively used in Gynaecology/Obstetrics and Law, while the Compound Unit Title dominated the Business titles. Syntactically, Noun Phrases extremely dominated the Single Unit Titles across the three domains. Detailed examination of the NP modifications showed that nominal titles which were both Pre and Post-modified were highly frequent in all the disciplines, which contrasts what is in the literature. The study also identified the Prepositional Phrase as the commonest structure used in post-modifying the nominal structures than using non-finite clauses in all the disciplines. Again, colon was the most predominant punctuation mark used in partitioning the Compound Unit Titles across the three disciplines, with Law recording the highest followed by Gynaecology/Obstetrics and Business. Lastly, the data exhibited high frequency of Domain-Specific words in the titles more than Research-Based words across the disciplines. This study provides useful information on the nature of effective RA titles to novice writers and advanced authors. It also informs the teaching of academic writing skills.

The study investigated the differential response to a single bout of maximal incremental treadmill exercise between athletes and non-athletes without dry eyes regarding tear secretion, tear film stability, visual acuity (VA), and stereoacuity. Additionally, the study examined the effect of gender and the duration of exercise on exercise-induced changes. Study participants included young university students aged 18-25 years who were athletes (male/female: 13/13) or non-athletes (male/female: 17/9). Participants underwent an aerobic exercise session using a treadmill and following the laid down Bruce treadmill test protocol till exhaustion. Measurements were taken in the order of distance VA, stereopsis, non-invasive tear break-up time (TBUT), and phenol red thread test, at baseline and after the exercise regimen. Within- and between-subject analyses using multiple t-tests with correction for multiple comparisons were performed to determine differences before and after exercise in athletes and non-athletes. Subsequently, ANCOVA was used to assess the influence of gender and the duration of exercise. The mean age (SD) of the athletes and the non-athletes was 22.4 ± 2.1 years and 21.8 ± 2.1 years, respectively (p = 0.357). Before exercise, the athletes had higher TBUT than non-athletes (14.6 ± 2.9 seconds vs. 11.9 ± 3.8 seconds; p = 0.021), but no difference was observed in any other ocular measurements. After exercise, the athletes showed significant improvement in tear secretion with the basal tear secretion increasing from 22.3 ± 2.5 mm to 25.8 ± 1.7 mm (p

the study’s objective was to assess the impact of human resource cost thus staff cost on profitability of firms. The scope of the study was listed companies on Ghana Stock Exchange and it selected 42 listed companies as its sample for a period five years from 2014 to 2018. The study employed non-probability sampling technique thus convenient sampling to select the companies used due to availability of data. As the study used exploratory method, it used panel data methodologies to arrive at its conclusion. These methodologies used are unit root, cointegration test, correlation matrix, censored tobit regression method and robust least square regression method. In summary, the study found out that human resource cost thus staff cost negatively relate to profitability of companies in Ghana statistically. As the argument as to whether human resources of organizations should be considered as assets in order to value their productivity rather than being part of organizations expenditures which one way or the other affects their profitability

Ghana has two seaports; Tema and Takoradi and since their inception in 1928 and 1963 respectively, these ports have undergone a lot of reforms all with the aim of making them effective and efficient to compete favourably with other ports in the world and also help increase the revenue of the government. Ghana Community Network (GCNet) introduced by the government of Ghana with their trading partners West Blue in 2003 was solely responsible for the collection of revenue at the two seaports in Ghana. Through the hard work of West Blue, most of the internal processes of doing business at the ports of Ghana were synchronized into one system thus making Ghana ports to go paperless on 1st September, 2017. However, on 30th May, 2020 GCNet was asked to shut down their operations at the ports of Ghana, a new software or system called UNIPASS/ ICUMS owned by Ghana link network services and CUPIA were asked to take over. This did not go down very well with most of the stakeholders involved in the clearing chain at the ports of Ghana thus leading to a whole lot of protests and demonstrations at the ports. This study therefore sought to delve into finding out what the challenges were with respect to using the UNIPASS/ ICUMS and then offer solutions to curtail any future eventualities any time a new software or system is being introduced at the ports of Ghana for clearing goods and doing business.

Objective The association between unbalanced iron indices and the conditions of schizophrenia are not well understood. Liver dysfunction which has been linked to iron metabolism might be a contributing factor. This case–control study evaluated serum iron indices and liver function in treatment-naïve schizophrenia patients and those already on treatment at the Psychiatric Department of the Komfo Anokye Teaching Hospital (KATH), Kumasi-Ghana. Results The mean age of the respondents was 39.6 ± 0.8 years. Increased levels of serum iron, TS, AST, ALT and AST:ALT ratio and lower levels of UIBC, TIBC, Transferrin, and log Ferritin:AST ratio levels were observed among the treatment-naïve group compared to the control. The treatment-naïve and treatment groups showed significantly higher serum AST:ALT ratio, and lower log10ferrtin:AST ratio than the healthy controls. There was a significant correlation between log10ferritin and AST, and log10ferritin and GGT in both treatments (r = 0.343; p = 0.003, and r = 0.502; p = 0.001 respectively) and treatment-naïve groups (r = 0.348; p = 0.002, and r = 0.614; p

Additional file 1: Table S1. Partial Pearson correlation between Iron markers and liver function markers among study participants.

Studies have proven that volatilities in the rates of exchange and interest influence the performance of institutions and the values of their shares. This study investigates empirically the effect of exchange rate and interest rate volatilities on stock prices of financial institutions listed on the Ghana Stock Exchange using monthly data spanning the period January 2000 to October 2016. The generalized auto regressive conditionality heteroskedastic (GARCH) model is employed for the analysis. The results show that exchange rate volatility exerts positive effect on stock prices whereas interest rate volatility impacts on stock prices negatively. These results imply that the trade-off between risk and return can be predicted so industry players and stakeholders can manage risk to ensure a vibrant financial market. It is also suggested that there is the need for stakeholders and policy makers to ensure that these variables are stable or the volatilities are minimized in the economy. This will go a long way to enhance the performance of the stock market activities in the country.

Background Little is known about the course of perinatal anxiety, particularly in low and middle income countries. This study aimed at examining trajectories of ante- and postpartum generalized anxiety symptoms in West-African women and their associations with mother and child characteristics. Methods 778 women from Cote d’Ivoire and Ghana were investigated between 04/2010 and 03/2014. Anxiety symptoms were measured using the seven-item Generalized Anxiety Disorder scale (GAD-7) at three months antepartum and three, 12 and 24 months postpartum. Growth mixture modeling was applied to identify latent trajectory classes of anxiety. Multinomial logistic regression was used to investigate the associations of psychosocial, sociodemographic, obstetric and clinical characteristics with different trajectories. Results Four distinct trajectories of anxiety were identified. The majority of women (79.8%) had consistent low anxiety symptoms, while 11.4% had elevated anxiety scores before and around childbirth that decreased gradually. 5.4% of women showed increasing anxiety symptoms over time. Few women (3.3%) had transient anxiety with elevated scores at three and 12 months postpartum. Risk factors for elevated anxiety levels around childbirth were antepartum depressive symptoms, higher levels of stress (economic, marital and social stress), lower child birth weight, and multiparity. Partner support was found to be protective. Limitations Anxiety symptoms were assessed using a screening instrument and not through a formal diagnostic classification system. Some putative risk factors were not investigated, and some psychosocial factors were assessed retrospectively. Conclusion The presence of different trajectories underline the importance of monitoring anxiety symptoms in pregnant women and in mothers with infants/toddlers.

The Role of benchmarking in the pharmaceutical industry was the topic for the research work. Tobinco Pharmaceutical Company Limited was chosen as the case of study. Both qualitative and quantitative techniques were used. The findings of the research revealed that majority of the workers at Tobinco Company limited were male, besides that the workers fell within the active labour force and were mostly educated up to the tertiary level. The research also outlined quality, customer care, packaging, marketing and purchasing as some of the key areas or activities benchmarked by Tobinco Pharmaceutical Company Limited. There were a lot of benefits that Tobinco Pharmaceutical Company Limited derived from benchmarking their activities, some of these included elimination of guess work, improves productivity, competitive advantage and many others. Equally, the research also outlined some challenges Tobinco Pharmaceutical Company Limited go through in benchmarking their activities, notably are difficulties in finding suitable partners, difficulties in comparing data, resource constrains (finance, time and expertise) and staff resistance. The research finally ended with a lot of good recommendations such as Tobinco Pharmaceutical Company Limited should go beyond the source of Ghana and look for other suitable pharmaceutical companies to benchmark, since it is difficult finding suitable partners in Ghana especially because they all import without manufacturing.

The importance of Fc-dependent effector functions of Abs induced by vaccination is increasingly recognized. However, vaccination of mice against HIV envelope (Env) induced a skewed Th cell response leading to Env-specific Abs with reduced effector function. To overcome this bias, GagPol-specific Th cells were harnessed to provide intrastructural help for Env-specific B cells after immunization with virus-like particles containing GagPol and Env. This led to a balanced Env-specific humoral immune response with a more inflammatory Fc glycan profile. The increased quality in the Ab response against Env was confirmed by FcγR activation assays. Because the Env-specific Th cell response was also biased in human vaccinees, intrastructural help is an attractive novel approach to increase the efficacy of prophylactic HIV Env-based vaccines and may also be applicable to other particulate vaccines.

Glycosylation of the Fc domain is an important driver of antibody effector function. While assessment of antibody glycoform compositions observed across total plasma IgG has identified differences associated with a variety of clinical conditions, in many cases it is the glycosylation state of only antibodies against a specific antigen or set of antigens that may be of interest, for example, in defining the potential effector function of antibodies produced during disease or after vaccination. Historically, glycoprofiling such antigen-specific antibodies in clinical samples has been challenging due to their low prevalence, the high sample requirement for most methods of glycan determination, and the lack of high-throughput purification methods. New methods of glycoprofiling with lower sample requirements and higher throughput have motivated the development of microscale and automatable methods for purification of antigen-specific antibodies from polyclonal sources such as clinical serum samples. In this work, we present a robot-compatible 96-well plate-based method for purification of antigen-specific antibodies, suitable for such population level glycosylation screening. We demonstrate the utility of this method across multiple antibody sources, using both purified plasma IgG and plasma, and across multiple different antigen types, with enrichment factors greater than 1000-fold observed. Using an on-column IdeS protease treatment, we further describe staged release of Fc and Fab domains, allowing for glycoprofiling of each domain.

As antibodies continue to gain predominance in drug discovery and development pipelines, efforts to control and optimize their activity in vivo have matured to incorporate sophisticated abilities to manipulate engagement of specific Fc binding partners. Such efforts to promote diverse functional outcomes include modulating IgG-Fc affinity for FcγRs to alternatively potentiate or reduce effector functions, such as antibody-dependent cellular cytotoxicity and phagocytosis. While a number of natural and engineered Fc features capable of eliciting variable effector functions have been demonstrated in vitro and in vivo, elucidation of these important functional relationships has taken significant effort through use of diverse genetic, cellular and enzymatic techniques. As an orthogonal approach, we demonstrate use of FcγR as chromatographic affinity ligands to enrich and therefore simultaneously identify favored binding species from a complex mixture of serum-derived pooled polycloncal human IgG, a load material that contains the natural repertoire of Fc variants and post-translational modifications. The FcγR-enriched IgG was characterized for subclass and glycoform composition and the impact of this bioseparation step on antibody activity was measured in cell-based effector function assays including Natural Killer cell activation and monocyte phagocytosis. This work demonstrates a tractable means to rapidly distinguish complex functional relationships between two or more interacting biological agents by leveraging affinity chromatography followed by secondary analysis with high-resolution biophysical and functional assays and emphasizes a platform capable of surveying diverse natural post-translational modifications that may not be easily produced with high purity or easily accessible with recombinant expression techniques.